1
|
Johnson CE, Duncan MJ, Murphy MP. Sex and Sleep Disruption as Contributing Factors in Alzheimer's Disease. J Alzheimers Dis 2024; 97:31-74. [PMID: 38007653 PMCID: PMC10842753 DOI: 10.3233/jad-230527] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2023]
Abstract
Alzheimer's disease (AD) affects more women than men, with women throughout the menopausal transition potentially being the most under researched and at-risk group. Sleep disruptions, which are an established risk factor for AD, increase in prevalence with normal aging and are exacerbated in women during menopause. Sex differences showing more disrupted sleep patterns and increased AD pathology in women and female animal models have been established in literature, with much emphasis placed on loss of circulating gonadal hormones with age. Interestingly, increases in gonadotropins such as follicle stimulating hormone are emerging to be a major contributor to AD pathogenesis and may also play a role in sleep disruption, perhaps in combination with other lesser studied hormones. Several sleep influencing regions of the brain appear to be affected early in AD progression and some may exhibit sexual dimorphisms that may contribute to increased sleep disruptions in women with age. Additionally, some of the most common sleep disorders, as well as multiple health conditions that impair sleep quality, are more prevalent and more severe in women. These conditions are often comorbid with AD and have bi-directional relationships that contribute synergistically to cognitive decline and neuropathology. The association during aging of increased sleep disruption and sleep disorders, dramatic hormonal changes during and after menopause, and increased AD pathology may be interacting and contributing factors that lead to the increased number of women living with AD.
Collapse
Affiliation(s)
- Carrie E. Johnson
- University of Kentucky, College of Medicine, Department of Molecular and Cellular Biochemistry, Lexington, KY, USA
| | - Marilyn J. Duncan
- University of Kentucky, College of Medicine, Department of Neuroscience, Lexington, KY, USA
| | - M. Paul Murphy
- University of Kentucky, College of Medicine, Department of Molecular and Cellular Biochemistry, Lexington, KY, USA
- University of Kentucky, Sanders-Brown Center on Aging, Lexington, KY, USA
| |
Collapse
|
2
|
Tan B, Yaşar A, Boz F, Dursun N, Süer C. Sex-related differences in somatic plasticity and possible role of ERK1/2: An in-vivo study of young-adult rats. Physiol Behav 2022; 255:113939. [PMID: 35961608 DOI: 10.1016/j.physbeh.2022.113939] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2022] [Revised: 07/29/2022] [Accepted: 08/08/2022] [Indexed: 11/19/2022]
Abstract
The present study investigates sex differences in hippocampal functions in the context of synaptic plasticity, which is the cellular basis of learning and memory, and differences in the mitogen-activated protein kinase (MAPK) pathway that accompanies plasticity in young-adult rats. The long-term potentiation (LTP) and long-term depression (LTD) were induced by stimulating the perforant pathway (PP) and field potentials composed of the field excitatory post-synaptic potential (fEPSP) and population spike (PS) were recorded from the dentate gyrus (DG). Following the completion of the electrophysiological recordings, the hippocampi were removed bilaterally, and the protein and gene expression levels of the extracellular signal-regulated kinase 1/2 (ERK1/2), c-Jun N-terminal kinase (JNK) and P38-MAPK were determined by Western blot analysis and real-time PCR, respectively. No significant difference was found in synaptic and neuronal function before (basal) and after high-frequency stimulation between male and female rats. Nevertheless, female, but not male, rats were able to express long term depression at the PP - DG synapses, suggesting that sex differences in plasticity are stimulation paradigm specific. MAPK1 expression was higher in males and MAPK3 expression was higher in females, but these differences disappeared after induction of plasticity in both sexes. While the expression of MAPK8 is influenced by sex, independent of the induction of plasticity, MAPK14 expression was down regulated by plasticity induction in females, but not males. No effect of sex, HFS and LFS on total and phosphorylated levels of MAPKs was found except phosphorylated ERK1/2. Phosphorylation of ERK1/2 was up regulated after LFS in male rats but did not change in female rats. These findings indicate that LFS-induced plasticity is differentially modulated between sexes, probably as a result of increased activation of ERK1/2 in male rats.
Collapse
Affiliation(s)
- Burak Tan
- Faculty of Medicine, Department of Physiology, Erciyes University, Kayseri, Turkey.
| | - Aslınur Yaşar
- Faculty of Medicine, Department of Physiology, Erciyes University, Kayseri, Turkey.
| | - Fatma Boz
- Faculty of Medicine, Department of Physiology, Erciyes University, Kayseri, Turkey.
| | - Nurcan Dursun
- Faculty of Medicine, Department of Physiology, Erciyes University, Kayseri, Turkey.
| | - Cem Süer
- Faculty of Medicine, Department of Physiology, Erciyes University, Kayseri, Turkey.
| |
Collapse
|
3
|
Behl T, Kaur D, Sehgal A, Singla RK, Makeen HA, Albratty M, Alhazmi HA, Meraya AM, Bungau S. Therapeutic insights elaborating the potential of retinoids in Alzheimer’s disease. Front Pharmacol 2022; 13:976799. [PMID: 36091826 PMCID: PMC9453874 DOI: 10.3389/fphar.2022.976799] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2022] [Accepted: 07/18/2022] [Indexed: 11/24/2022] Open
Abstract
Alzheimer’s disease (AD) is perceived with various pathophysiological characteristics such oxidative stress, senile plaques, neuroinflammation, altered neurotransmission immunological changes, neurodegenerative pathways, and age-linked alterations. A great deal of studies even now are carried out for comprehensive understanding of pathological processes of AD, though many agents are in clinical trials for the treatment of AD. Retinoids and retinoic acid receptors (RARs) are pertinent to such attributes of the disease. Retinoids support the proper functioning of the immunological pathways, and are very potent immunomodulators. The nervous system relies heavily on retinoic acid signaling. The disruption of retinoid signaling relates to several pathogenic mechanisms in the normal brain. Retinoids play critical functions in the neuronal organization, differentiation, and axonal growth in the normal functioning of the brain. Disturbed retinoic acid signaling causes inflammatory responses, mitochondrial impairment, oxidative stress, and neurodegeneration, leading to Alzheimer’s disease (AD) progression. Retinoids interfere with the production and release of neuroinflammatory chemokines and cytokines which are located to be activated in the pathogenesis of AD. Also, stimulating nuclear retinoid receptors reduces amyloid aggregation, lowers neurodegeneration, and thus restricts Alzheimer’s disease progression in preclinical studies. We outlined the physiology of retinoids in this review, focusing on their possible neuroprotective actions, which will aid in elucidating the critical function of such receptors in AD pathogenesis.
Collapse
Affiliation(s)
- Tapan Behl
- School of Health Sciences, University of Petroleum and Energy Studies, Dehradun, Uttarakhand, India
- *Correspondence: Tapan Behl, ; Simona Bungau,
| | - Dapinder Kaur
- Chitkara College of Pharmacy, Chitkara University, Rajpura, Punjab, India
| | - Aayush Sehgal
- Chitkara College of Pharmacy, Chitkara University, Rajpura, Punjab, India
| | - Rajeev K. Singla
- Institutes for Sytems Genetics, Frontiers Science Center for Disease-Related Molecular Network, West China Hospital, Sichuan University, Chengdu, Sichuan, China
- iGlobal Research and Publishing Foundation, New Delhi, India
| | - Hafiz A. Makeen
- Pharmacy Practice Research Unit, Clinical Pharmacy Department, College of Pharmacy, Jazan University, Jazan, Saudi Arabia
| | - Mohammed Albratty
- Department of Pharmaceutical Chemistry and Pharmacognosy, College of Pharmacy, Jazan University, Jazan, Saudi Arabia
| | - Hassan A. Alhazmi
- Department of Pharmaceutical Chemistry and Pharmacognosy, College of Pharmacy, Jazan University, Jazan, Saudi Arabia
- Substance Abuse and Toxicology Research Center, Jazan University, Jazan, Saudi Arabia
| | - Abdulkarim M. Meraya
- Pharmacy Practice Research Unit, Department of Clinical Pharmacy, College of Pharmacy, Jazan University, Jazan, Saudi Arabia
| | - Simona Bungau
- Department of Pharmacy, Faculty of Medicine and Pharmacy, University of Oradea, Oradea, Romania
- Doctoral School of Biomedical Sciences, University of Oradea, Oradea, Romania
- *Correspondence: Tapan Behl, ; Simona Bungau,
| |
Collapse
|
4
|
McQuail JA, Dunn AR, Stern Y, Barnes CA, Kempermann G, Rapp PR, Kaczorowski CC, Foster TC. Cognitive Reserve in Model Systems for Mechanistic Discovery: The Importance of Longitudinal Studies. Front Aging Neurosci 2021; 12:607685. [PMID: 33551788 PMCID: PMC7859530 DOI: 10.3389/fnagi.2020.607685] [Citation(s) in RCA: 33] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2020] [Accepted: 12/30/2020] [Indexed: 12/14/2022] Open
Abstract
The goal of this review article is to provide a resource for longitudinal studies, using animal models, directed at understanding and modifying the relationship between cognition and brain structure and function throughout life. We propose that forthcoming longitudinal studies will build upon a wealth of knowledge gleaned from prior cross-sectional designs to identify early predictors of variability in cognitive function during aging, and characterize fundamental neurobiological mechanisms that underlie the vulnerability to, and the trajectory of, cognitive decline. Finally, we present examples of biological measures that may differentiate mechanisms of the cognitive reserve at the molecular, cellular, and network level.
Collapse
Affiliation(s)
- Joseph A McQuail
- Department of Pharmacology, Physiology and Neuroscience, University of South Carolina School of Medicine, Columbia, SC, United States
| | - Amy R Dunn
- The Jackson Laboratory, Bar Harbor, ME, United States
| | - Yaakov Stern
- Cognitive Neuroscience Division, Department of Neurology, Vagelos College of Physicians and Surgeons, Columbia University, New York, NY, United States
| | - Carol A Barnes
- Departments of Psychology and Neuroscience, University of Arizona, Tucson, AZ, United States.,Evelyn F. McKnight Brain Institute, University of Arizona, Tucson, AZ, United States
| | - Gerd Kempermann
- CRTD-Center for Regenerative Therapies Dresden, Technische Universität Dresden, Dresden, Germany.,German Center for Neurodegenerative Diseases (DZNE), Helmholtz Association of German Research Centers (HZ), Dresden, Germany
| | - Peter R Rapp
- Laboratory of Behavioral Neuroscience, Neurocognitive Aging Section, National Institute on Aging, Baltimore, MD, United States
| | | | - Thomas C Foster
- Department of Neuroscience, McKnight Brain Institute, University of Florida, Gainesville, FL, United States.,Genetics and Genomics Program, University of Florida, Gainesville, FL, United States
| |
Collapse
|
5
|
Dorsey A, de Lecea L, Jennings KJ. Neurobiological and Hormonal Mechanisms Regulating Women's Sleep. Front Neurosci 2021; 14:625397. [PMID: 33519372 PMCID: PMC7840832 DOI: 10.3389/fnins.2020.625397] [Citation(s) in RCA: 21] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2020] [Accepted: 12/22/2020] [Indexed: 01/22/2023] Open
Abstract
Sleep is crucial for optimal well-being, and sex differences in sleep quality have significant implications for women's health. We review the current literature on sex differences in sleep, such as differences in objective and subjective sleep measures and their relationship with aging. We then discuss the convincing evidence for the role of ovarian hormones in regulating female sleep, and survey how these hormones act on a multitude of brain regions and neurochemicals to impact sleep. Lastly, we identify several important areas in need of future research to narrow the knowledge gap and improve the health of women and other understudied populations.
Collapse
Affiliation(s)
| | | | - Kimberly J. Jennings
- Department of Psychiatry and Behavioral Sciences, School of Medicine, Stanford University, Stanford, CA, United States
| |
Collapse
|
6
|
Kumar M, Sandhir R. Hydrogen sulfide suppresses homocysteine-induced glial activation and inflammatory response. Nitric Oxide 2019; 90:15-28. [DOI: 10.1016/j.niox.2019.05.008] [Citation(s) in RCA: 29] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2018] [Revised: 04/30/2019] [Accepted: 05/26/2019] [Indexed: 11/26/2022]
|
7
|
Modulation of the p75 neurotrophin receptor suppresses age-related basal forebrain cholinergic neuron degeneration. Sci Rep 2019; 9:5273. [PMID: 30918278 PMCID: PMC6437186 DOI: 10.1038/s41598-019-41654-8] [Citation(s) in RCA: 21] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2018] [Accepted: 02/08/2019] [Indexed: 11/19/2022] Open
Abstract
Age-related degeneration of basal forebrain cholinergic neurons (BFCNs) is linked to cognitive impairment. The p75 neurotrophin receptor (p75NTR) has been proposed to mediate neuronal degeneration in aging. Therefore, we tested the hypothesis that modifying p75NTR function would prevent or reverse aging-related neuronal degeneration using LM11A-31, a small molecule p75NTR modulator that downregulates degenerative and upregulates trophic receptor-associated signaling. Morphological analysis in mice showed loss of BFCN area detectable by 18 months of age. Oral administration of LM11A-31 from age 15 to 18 months resulted in a dose-related preservation of BFCN area and one month of treatment from 17 to 18 months also preserved cell area. To evaluate reversal of established neuronal atrophy, animals were treated from 21 to 25 months of age. Treatment was associated with an increase of cell size to a mean area larger than that observed at 18 months, accompanied by increases in mean MS/VDB neurite length, as well as increased cholinergic fiber density and synaptophysin pre-synaptic marker levels in the hippocampus. These findings support the idea that modulation of p75NTR activity can prevent and potentially reverse age-associated BFCN degeneration. Moreover, this may be achieved therapeutically with orally bioavailable agents such as LM11A-31.
Collapse
|
8
|
Ren D, Zhao F, Liu C, Wang J, Guo Y, Liu J, Min W. Antioxidant hydrolyzed peptides from Manchurian walnut (Juglans mandshurica Maxim.) attenuate scopolamine-induced memory impairment in mice. JOURNAL OF THE SCIENCE OF FOOD AND AGRICULTURE 2018; 98:5142-5152. [PMID: 29652442 DOI: 10.1002/jsfa.9060] [Citation(s) in RCA: 40] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/04/2017] [Revised: 02/12/2018] [Accepted: 04/02/2018] [Indexed: 06/08/2023]
Abstract
BACKGROUND Walnut protein, which is obtained as a by-product of oil expression, has not been used efficiently. Although walnuts are beneficial for cognitive functioning, the potential of their protein composition in strengthening learning and memory functions remains unknown. In this study, the inhibition of memory impairment by the Manchurian walnut hydrolyzed peptide (MWHP) was evaluated. RESULTS Small-molecular-weight MWHP (<3 kDa) achieved the optimal antioxidative activity. Therefore, MWHP (<3 kDa) was subjected to the following mice trials to evaluate its attenuation effect on memory impairment. In the Morris water maze test, MWHP shortened the total path for searching the platform, reduced the escape latency, and increased the dwelling distance and time in the coverage zone. MWHP also prolonged the latency and diminished errors in the passive avoidance response tests. These behavioral tests demonstrated that MWHP could inhibit scopolamine-induced memory impairment. MWHP improved memory by reducing oxidative stress, inhibiting apoptosis, regulating neurotransmitter functions, maintaining hippocampal CA3 pyramidal neurons, and increasing calmodulin-dependent protein kinase II levels in brain tissues. CONCLUSION Experimental results proved that MWHP exhibits potential in improving memory and should be used to develop novel functional food. © 2018 Society of Chemical Industry.
Collapse
Affiliation(s)
- Dayong Ren
- College of Food Science and Engineering, Jilin Agricultural University, Changchun, Jilin, China
- National Engineering Laboratory on Wheat and Corn Further Processing, Changchun, Jilin, China
| | - Fanrui Zhao
- College of Food Science and Engineering, Jilin Agricultural University, Changchun, Jilin, China
- National Engineering Laboratory on Wheat and Corn Further Processing, Changchun, Jilin, China
| | - Chunlei Liu
- College of Food Science and Engineering, Jilin Agricultural University, Changchun, Jilin, China
- National Engineering Laboratory on Wheat and Corn Further Processing, Changchun, Jilin, China
| | - Ji Wang
- College of Food Science and Engineering, Jilin Agricultural University, Changchun, Jilin, China
- National Engineering Laboratory on Wheat and Corn Further Processing, Changchun, Jilin, China
| | - Yong Guo
- College of Food Science and Engineering, Jilin Agricultural University, Changchun, Jilin, China
- National Engineering Laboratory on Wheat and Corn Further Processing, Changchun, Jilin, China
| | - Jingsheng Liu
- College of Food Science and Engineering, Jilin Agricultural University, Changchun, Jilin, China
- National Engineering Laboratory on Wheat and Corn Further Processing, Changchun, Jilin, China
| | - Weihong Min
- College of Food Science and Engineering, Jilin Agricultural University, Changchun, Jilin, China
- National Engineering Laboratory on Wheat and Corn Further Processing, Changchun, Jilin, China
| |
Collapse
|
9
|
Zhang Y, Mao X, Lin R, Li Z, Lin J. Electroacupuncture ameliorates cognitive impairment through inhibition of Ca 2+-mediated neurotoxicity in a rat model of cerebral ischaemia-reperfusion injury. Acupunct Med 2018; 36:401-407. [PMID: 30257960 PMCID: PMC6287559 DOI: 10.1136/acupmed-2016-011353] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 10/22/2017] [Indexed: 01/05/2023]
Abstract
Background The hippocampus is vulnerable to severe damage after cerebral ischaemia–reperfusion (I/R) injury. This study aimed to explore the effect of electroacupuncture (EA) on cognitive impairment and its relationship with Ca2+neurotoxicity in a rat model of I/R injury induced by middle cerebral artery occlusion (MCAO). Methods 60 adult male Sprague-Dawley rats were randomly divided into three groups: control (sham surgery) group, untreated MCAO group and EA-treated MCAO+EA group. Rats in the MCAO and MCAO+EA groups underwent modelling of poststroke cognitive impairment by MCAO surgery. EA was performed for 30 min daily at GV20 and GV24 (1–20 Hz) for 1 week. The Morris water maze experiment was used to assess cognitive function. 2,3,5-triphenyl tetrazolium chloride staining was used to measure infarct volume. The intracellular Ca2+content in the Cornu Ammonis (CA)1 area of the hippocampus was assessed by laser confocal scanning microscopy. ELISA was performed to evaluate the concentration of glutamate (Glu) in the hippocampus, and the protein expression of two Glu receptors (N-methyl-D-aspartic acid receptor (NMDAR) 2A and NMDAR2B) were analysed by Western blotting. Results Compared with the untreated MCAO group, EA effectively ameliorated cognitive impairment (P=0.01) and shrunk the infarct volume (P=0.032). The content of intracellular Ca2+, Glu and NMDAR2B in the hippocampus was significantly raised by MCAO (P=0.031-0.043), while EA abrogated these effects. NMDAR2A was decreased by MCAO (P=0.015) but increased by EA (P=0.033). Conclusions EA had a beneficial effect on cognitive repair after cerebral I/R, and its mechanism of action likely involves a reduction of Ca2+influx via inhibition of Glu neurotoxicity and downregulation of NMDAR2B expression.
Collapse
Affiliation(s)
- Yun Zhang
- Clinical Medicine Department, Fujian Health College, Fuzhou, China
| | - Xiang Mao
- Acupuncture Department, Chongqing Traditional Chinese Medicine Hospital, Chongqing, China
| | - Ruhui Lin
- Academy of Integrative Medicine, Fujian University of Traditional Chinese Medicine, Fuzhou, China
| | - Zuanfang Li
- Academy of Integrative Medicine, Fujian University of Traditional Chinese Medicine, Fuzhou, China
| | - Jing Lin
- Clinical Medicine Department, Fujian Health College, Fuzhou, China
| |
Collapse
|
10
|
He J, Zhao C, Liu W, Huang J, Liang S, Chen L, Tao J. Neurochemical changes in the hippocampus and prefrontal cortex associated with electroacupuncture for learning and memory impairment. Int J Mol Med 2017; 41:709-716. [PMID: 29207061 PMCID: PMC5752233 DOI: 10.3892/ijmm.2017.3287] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2016] [Accepted: 10/27/2017] [Indexed: 01/19/2023] Open
Abstract
Electroacupuncture (EA) has been widely used to treat cognitive impairment following cerebral ischemia. However, the functional mechanisms of EA have not been fully elucidated. The aim of the present study was to investigate whether EA at the GV 20 and DU 24 acupoints can improve the learning and memory ability via alteration of the neurochemical metabolism in the hippocampus (HPC) and prefrontal cortex (PFC) of rats with ischemia and reperfusion (I/R) injury. Sprague-Dawley male rats were randomly divided into three groups, namely the sham group (n=12), the middle cerebral artery occlusion (MCAO) group (n=12) and the EA treatment (MCAO + EA) group (n=12). MCAO was performed to establish the left focal cerebral I/R injury model, and the GV 20 and DU 24 acupoints were then stimulated with EA for 30 min per time, once daily, for 7 consecutive days. The Morris water maze (MWM) test was used to assess learning and memory ability. T2-weighted imaging was used to assess the cerebral infarct volume. Magnetic resonance spectroscopy was used to assess neurochemical metabolism of HPC and PFC. The neurological scores of the MCAO + EA group were significantly reduced compared with those of the MCAO group 7 days after EA treatment (P<0.01). The escape latency of the MWM test in the MCAO + EA group was found to be shorter compared with that in the MCAO group (P<0.01). The number of rats crossing through the platform area was significantly higher in the MCAO + EA group compared with that in the MCAO group (P<0.01). The cerebral infarct volume was also decreased in the MCAO + EA group compared with the MCAO group (P<0.05). The ratios of N-acetylaspartate (NAA)/creatine (Cr) and choline (Cho)/Cr of left-to-right HPC were increased in the MCAO + EA group compared with the MCAO group; however, the ratio of glutamate (Glu)/Cr did not change significantly (P>0.05). The ratios of NAA/Cr, Cho/Cr and Glu/Cr of left-to-right PFC were elevated (P<0.05). In conclusion, EA at the GV 20 and DU 24 acupoints may ameliorate learning and memory ability, possibly through increasing the levels of NAA and Cho in the HPC and PFC of rats with I/R injury.
Collapse
Affiliation(s)
- Jian He
- College of Rehabilitation Medicine, Fujian University of Traditional Chinese Medicine, Fuzhou, Fujian 350122, P.R. China
| | - Congkuai Zhao
- Fujian Key Laboratory of Rehabilitation Technology, Fuzhou, Fujian 350003, P.R. China
| | - Weilin Liu
- College of Rehabilitation Medicine, Fujian University of Traditional Chinese Medicine, Fuzhou, Fujian 350122, P.R. China
| | - Jia Huang
- College of Rehabilitation Medicine, Fujian University of Traditional Chinese Medicine, Fuzhou, Fujian 350122, P.R. China
| | - Shengxiang Liang
- College of Physical Science and Technology, Zhengzhou University, Zhengzhou, Henan 450001, P.R. China
| | - Lidian Chen
- College of Rehabilitation Medicine, Fujian University of Traditional Chinese Medicine, Fuzhou, Fujian 350122, P.R. China
| | - Jing Tao
- College of Rehabilitation Medicine, Fujian University of Traditional Chinese Medicine, Fuzhou, Fujian 350122, P.R. China
| |
Collapse
|
11
|
Koebele SV, Bimonte-Nelson HA. The endocrine-brain-aging triad where many paths meet: female reproductive hormone changes at midlife and their influence on circuits important for learning and memory. Exp Gerontol 2016; 94:14-23. [PMID: 27979770 DOI: 10.1016/j.exger.2016.12.011] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2016] [Revised: 12/09/2016] [Accepted: 12/10/2016] [Indexed: 01/15/2023]
Abstract
Female mammals undergo natural fluctuations in sex steroid hormone levels throughout life. These fluctuations span from early development, to cyclic changes associated with the menstrual or estrous cycle and pregnancy, to marked hormone flux during perimenopause, and a final decline at reproductive senescence. While the transition to reproductive senescence is not yet fully understood, the vast majority of mammals experience this spontaneous, natural phenomenon with age, which has broad implications for long-lived species. Indeed, this post-reproductive life stage, and its transition, involves significant and enduring physiological changes, including considerably altered sex steroid hormone and gonadotropin profiles that impact multiple body systems, including the brain. The endocrine-brain-aging triad is especially noteworthy, as many paths meet and interact. Many of the brain regions affected by aging are also sensitive to changes in ovarian hormone levels, and aging and reproductive senescence are both associated with changes in memory performance. This review explores how menopause is related to cognitive aging, and discusses some of the key neural systems and molecular factors altered with age and reproductive hormone level changes, with an emphasis on brain regions important for learning and memory.
Collapse
Affiliation(s)
- Stephanie V Koebele
- Department of Psychology, Arizona State University, Tempe, AZ 85287, United States; Arizona Alzheimer's Consortium, Phoenix, AZ 85006, United States
| | - Heather A Bimonte-Nelson
- Department of Psychology, Arizona State University, Tempe, AZ 85287, United States; Arizona Alzheimer's Consortium, Phoenix, AZ 85006, United States.
| |
Collapse
|
12
|
Koss WA, Frick KM. Sex differences in hippocampal function. J Neurosci Res 2016; 95:539-562. [DOI: 10.1002/jnr.23864] [Citation(s) in RCA: 99] [Impact Index Per Article: 12.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2016] [Revised: 06/28/2016] [Accepted: 07/11/2016] [Indexed: 12/25/2022]
Affiliation(s)
- Wendy A. Koss
- Department of Psychology; University of Wisconsin-Milwaukee; Milwaukee Wisconsin
| | - Karyn M. Frick
- Department of Psychology; University of Wisconsin-Milwaukee; Milwaukee Wisconsin
| |
Collapse
|
13
|
Chakrabarti M, McDonald AJ, Will Reed J, Moss MA, Das BC, Ray SK. Molecular Signaling Mechanisms of Natural and Synthetic Retinoids for Inhibition of Pathogenesis in Alzheimer's Disease. J Alzheimers Dis 2016; 50:335-52. [PMID: 26682679 DOI: 10.3233/jad-150450] [Citation(s) in RCA: 35] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Abstract
Retinoids, which are vitamin A derivatives, interact through retinoic acid receptors (RARs) and retinoid X receptors (RXRs) and have profound effects on several physiological and pathological processes in the brain. The presence of retinoic acid signaling is extensively detected in the adult central nervous system, including the amygdala, cortex, hypothalamus, hippocampus, and other brain areas. Retinoids are primarily involved in neural patterning, differentiation, and axon outgrowth. Retinoids also play a key role in the preservation of the differentiated state of adult neurons. Impairment in retinoic acid signaling can result in neurodegeneration and progression of Alzheimer's disease (AD). Recent studies demonstrated severe deficiencies in spatial learning and memory in mice during retinoic acid (vitamin A) deprivation indicating its significance in preserving memory function. Defective cholinergic neurotransmission plays an important role in cognitive deficits in AD. All-trans retinoic acid is known to enhance the expression and activity of choline acetyltransferase in neuronal cell lines. Activation of RAR and RXR is also known to impede the pathogenesis of AD in mice by inhibiting accumulation of amyloids. In addition, retinoids have been shown to inhibit the expression of chemokines and pro-inflammatory cytokines in microglia and astrocytes, which are activated in AD. In this review article, we have described the chemistry and molecular signaling mechanisms of natural and synthetic retinoids and current understandings of their therapeutic potentials in prevention of AD pathology.
Collapse
Affiliation(s)
- Mrinmay Chakrabarti
- Department of Pathology, Microbiology, and Immunology, University of South Carolina School of Medicine, Columbia, SC, USA
| | - Alexander J McDonald
- Department of Pharmacology, Physiology, and Neuroscience, University of South Carolina School of Medicine, Columbia, SC, USA
| | - J Will Reed
- Department of Chemical Engineering, University of South Carolina, Columbia, SC, USA
| | - Melissa A Moss
- Department of Chemical Engineering, University of South Carolina, Columbia, SC, USA
| | - Bhaskar C Das
- Division of Hematology and Oncology, University of Kansas Medical Center, Kansas City, KS, USA
| | - Swapan K Ray
- Department of Pathology, Microbiology, and Immunology, University of South Carolina School of Medicine, Columbia, SC, USA
| |
Collapse
|
14
|
Davis RL, Weisbeck C. Search Strategies Used by Older Adults in a Virtual Reality Place Learning Task. THE GERONTOLOGIST 2016; 55 Suppl 1:S118-27. [PMID: 26055772 DOI: 10.1093/geront/gnv020] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
PURPOSE OF THE STUDY Older adults often have problems finding their way in novel environments such as senior living residences and hospitals. The purpose of this study was to examine the types of self-reported search strategies and cues that older adults use to find their way in a virtual maze. DESIGN AND METHODS Healthy, independently living older adults (n = 129) aged 55-96 were tested in a virtual maze task over a period of 3 days in which they had to repeatedly find their way to a specified goal. They were interviewed about their strategies on days 1 and 3. Content analysis was used to identify the strategies and cues described by the participants in order to find their way. Strategies and cues used were compared among groups. RESULTS The participants reported the use of multiple spatial and non-spatial strategies, and some of the strategies differed among age groups and over time. The oldest age group was less likely to use strategies such as triangulation and distance strategies. All participants used visual landmarks to find their way, but the use of geometric cues (corners) was used less by the older participants. IMPLICATIONS These findings add to the theoretical understanding of how older adults find their way in complex environments. The understanding of how wayfinding changes with age is essential in order to design more supportive environments.
Collapse
Affiliation(s)
- Rebecca L Davis
- Kirkhof College of Nursing, Grand Valley State University, Grand Rapids, Michigan.
| | - Catherine Weisbeck
- Kirkhof College of Nursing, Grand Valley State University, Grand Rapids, Michigan
| |
Collapse
|
15
|
Detrimental effects of a high fat/high cholesterol diet on memory and hippocampal markers in aged rats. Behav Brain Res 2016; 312:294-304. [PMID: 27343935 DOI: 10.1016/j.bbr.2016.06.012] [Citation(s) in RCA: 67] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2016] [Revised: 06/03/2016] [Accepted: 06/07/2016] [Indexed: 01/22/2023]
Abstract
High fat diets have detrimental effects on cognitive performance, and can increase oxidative stress and inflammation in the brain. The aging brain provides a vulnerable environment to which a high fat diet could cause more damage. We investigated the effects of a high fat/high cholesterol (HFHC) diet on cognitive performance, neuroinflammation markers, and phosphorylated Tau (p-Tau) pathological markers in the hippocampus of Young (4-month old) versus Aged (14-month old) male rats. Young and Aged male Fisher 344 rats were fed a HFHC diet or a normal control diet for 6 months. All animals underwent cognitive testing for 12days in a water radial arm maze to assess spatial and working reference memory. Hippocampal tissue was analyzed by immunohistochemistry for structural changes and inflammation, and Western blot analysis. Young and Aged rats fed the HFHC diet exhibited worse performance on a spatial working memory task. They also exhibited significant reduction of NeuN and calbindin-D28k immunoreactivity as well as an increased activation of microglial cells in the hippocampal formation. Western blot analysis of the hippocampus showed higher levels of p-Tau S202/T205 and T231 in Aged HFHC rats, suggesting abnormal phosphorylation of Tau protein following the HFHC diet exposure. This work demonstrates HFHC diet-induced cognitive impairment with aging and a link between high fat diet consumption and pathological markers of Alzheimer's disease.
Collapse
|
16
|
Kaur H, Patro I, Tikoo K, Sandhir R. Curcumin attenuates inflammatory response and cognitive deficits in experimental model of chronic epilepsy. Neurochem Int 2015; 89:40-50. [DOI: 10.1016/j.neuint.2015.07.009] [Citation(s) in RCA: 64] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2015] [Revised: 07/12/2015] [Accepted: 07/14/2015] [Indexed: 12/20/2022]
|
17
|
Lin R, Lin Y, Tao J, Chen B, Yu K, Chen J, Li X, Chen LD. Electroacupuncture ameliorates learning and memory in rats with cerebral ischemia-reperfusion injury by inhibiting oxidative stress and promoting p-CREB expression in the hippocampus. Mol Med Rep 2015; 12:6807-14. [PMID: 26397995 DOI: 10.3892/mmr.2015.4321] [Citation(s) in RCA: 36] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/15/2014] [Accepted: 04/17/2015] [Indexed: 11/06/2022] Open
Abstract
The present study aimed to investigate the mechanisms by which electroacupuncture (EA) ameliorates learning and memory in rats with cerebral ischemic‑reperfusion (I/R) injury. Focal cerebral ischemia was induced in adult male Sprague‑Dawley (SD) rats by transient middle cerebral artery occlusion (MCAO). Following MCAO surgery, the rats received EA at the Shenting (DU24) and Baihui (DU20) acupoints. The results of the present study demonstrated that treatment with EA significantly ameliorated neurological deficits and reduced cerebral infarct volume (P<0.05). In addition, EA improved the learning and memory ability of the rats, and markedly activated the cyclic adenosine monophosphate (cAMP) response element‑binding protein (CREB) signaling pathway, resulting in the inhibition of cerebral cell apoptosis in the ischemic penumbra. Furthermore, EA increased the activity of superoxide dismutase and glutathione peroxidase, the protein expression levels of phosphorylated‑CREB and B‑cell lymphoma 2 (Bcl‑2), and the mRNA expression levels of Bcl‑2. Conversely, EA decreased the levels of malondialdehyde and inhibited the expression levels of Bcl2‑associated X protein. The results of the present study suggest that treatment with EA may result in the amelioration of learning and memory ability in rats with cerebral I/R injury.
Collapse
Affiliation(s)
- Ruhui Lin
- College of Rehabilitation Medicine, Fujian University of Traditional Chinese Medicine, Fuzhou, Fujian 350122, P.R. China
| | - Yukun Lin
- College of Rehabilitation Medicine, Fujian University of Traditional Chinese Medicine, Fuzhou, Fujian 350122, P.R. China
| | - Jing Tao
- College of Rehabilitation Medicine, Fujian University of Traditional Chinese Medicine, Fuzhou, Fujian 350122, P.R. China
| | - Bin Chen
- TCM Rehabilitation Research Center of SATCM, Fujian University of Traditional Chinese Medicine, Fuzhou, Fujian 350122, P.R. China
| | - Kunqiang Yu
- Fujian Key Laboratory of Exercise Rehabilitation, Fujian University of Traditional Chinese Medicine, Fuzhou, Fujian 350122, P.R. China
| | - Jixiang Chen
- Fujian Key Laboratory of Exercise Rehabilitation, Fujian University of Traditional Chinese Medicine, Fuzhou, Fujian 350122, P.R. China
| | - Xiaojie Li
- Fujian Rehabilitation Tech Co‑innovation Center, Fujian University of Traditional Chinese Medicine, Fuzhou, Fujian 350122, P.R. China
| | - Li-Dian Chen
- College of Rehabilitation Medicine, Fujian University of Traditional Chinese Medicine, Fuzhou, Fujian 350122, P.R. China
| |
Collapse
|
18
|
Devan BD, Magalis C, McDonald RJ. Hippocampal development and the dissociation of cognitive-spatial mapping from motor performance. F1000Res 2015; 4:625. [PMID: 26594345 PMCID: PMC4648208 DOI: 10.12688/f1000research.6966.2] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 09/17/2015] [Indexed: 11/20/2022] Open
Abstract
The publication of a recent article in F1000Research has led to discussion of, and correspondence on a broader issue that has a long history in the fields of neuroscience and psychology. Namely, is it possible to separate the cognitive components of performance, in this case spatial behavior, from the motoric demands of a task? Early psychological experiments attempted such a dissociation by studying a form of spatial maze learning where initially rats were allowed to explore a complex maze, termed "latent learning," before reinforcement was introduced. Those rats afforded the latent learning experience solved the task faster than those that were not, implying that cognitive map learning during exploration aided in the performance of the task once a motivational component was introduced. This form of latent learning was interpreted as successfully demonstrating that an exploratory cognitive map component was acquired irrespective of performing a learned spatial response under deprivation/motivational conditions. The neural substrate for cognitive learning was hypothesized to depend on place cells within the hippocampus. Subsequent behavioral studies attempted to directly eliminate the motor component of spatial learning by allowing rats to passively view the distal environment before performing any motor response using a task that is widely considered to be hippocampal-dependent. Latent learning in the water maze, using a passive placement procedure has met with mixed results. One constraint on viewing cues before performing a learned swimming response to a hidden goal has been the act of dynamically viewing distal cues while moving through a part of the environment where an optimal learned spatial escape response would be observed. We briefly review these past findings obtained with adult animals to the recent efforts of establishing a "behavioral topology" separating cognitive-spatial learning from tasks differing in motoric demands in an attempt to define when cognitive-spatial behavior emerges during development.
Collapse
Affiliation(s)
- Bryan D Devan
- Psychology Department, Laboratory of Comparative Neuropsychology, Towson University, Towson, Maryland, 21252, USA
| | - Christopher Magalis
- Psychology Department, Laboratory of Comparative Neuropsychology, Towson University, Towson, Maryland, 21252, USA
| | - Robert J McDonald
- Department of Neuroscience, Canadian Center for Behavioural Neuroscience, University of Lethbridge, Lethbridge, Alberta, TIK 3M4, Canada
| |
Collapse
|
19
|
Luine VN. Estradiol and cognitive function: past, present and future. Horm Behav 2014; 66:602-18. [PMID: 25205317 PMCID: PMC4318702 DOI: 10.1016/j.yhbeh.2014.08.011] [Citation(s) in RCA: 290] [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: 06/06/2014] [Revised: 08/26/2014] [Accepted: 08/29/2014] [Indexed: 12/13/2022]
Abstract
A historical perspective on estradiol's enhancement of cognitive function is presented, and research, primarily in animals, but also in humans, is reviewed. Data regarding the mechanisms underlying the enhancements are discussed. Newer studies showing rapid effects of estradiol on consolidation of memory through membrane interactions and activation of inter-cellular signaling pathways are reviewed as well as studies focused on traditional genomic mechanisms. Recent demonstrations of intra-neuronal estradiol synthesis and possible actions as a neurosteroid to promote memory are discussed. This information is applied to the critical issue of the current lack of effective hormonal (or other) treatments for cognitive decline associated with menopause and aging. Finally, the critical period hypothesis for estradiol effects is discussed along with novel strategies for hormone/drug development. Overall, the historical record documents that estradiol positively impacts some aspects of cognitive function, but effective therapeutic interventions using this hormone have yet to be realized.
Collapse
Affiliation(s)
- Victoria N Luine
- Department of Psychology, Hunter College of CUNY, New York, NY, USA.
| |
Collapse
|
20
|
Potential therapeutic strategies for Alzheimer's disease targeting or beyond β-amyloid: insights from clinical trials. BIOMED RESEARCH INTERNATIONAL 2014; 2014:837157. [PMID: 25136630 PMCID: PMC4124758 DOI: 10.1155/2014/837157] [Citation(s) in RCA: 42] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/04/2014] [Revised: 06/23/2014] [Accepted: 06/25/2014] [Indexed: 01/25/2023]
Abstract
Alzheimer's disease (AD) is a progressive neurodegenerative disorder with two hallmarks: β-amyloid plagues and neurofibrillary tangles. It is one of the most alarming illnesses to elderly people. No effective drugs and therapies have been developed, while mechanism-based explorations of therapeutic approaches have been intensively investigated. Outcomes of clinical trials suggested several pitfalls in the choice of biomarkers, development of drug candidates, and interaction of drug-targeted molecules; however, they also aroused concerns on the potential deficiency in our understanding of pathogenesis of AD, and ultimately stimulated the advent of novel drug targets tests. The anticipated increase of AD patients in next few decades makes development of better therapy an urgent issue. Here we attempt to summarize and compare putative therapeutic strategies that have completed clinical trials or are currently being tested from various perspectives to provide insights for treatments of Alzheimer's disease.
Collapse
|
21
|
Rose GM, Rowe WB. Water maze testing to identify compounds for cognitive enhancement. ACTA ACUST UNITED AC 2013; Chapter 5:Unit 5.63. [PMID: 23258600 DOI: 10.1002/0471141755.ph0563s59] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
The water maze task is widely used to evaluate spatial learning and memory in rodents. The basic paradigm requires an animal to swim in a pool until it finds a hidden escape platform. The animals learn to find the platform using extra-maze cues and, after several training trials, are able to swim directly to it from any starting location. Memory for the platform location is assessed by examining swimming behavior with the platform removed from the maze, while sensory, motor and motivational aspects of the task can be examined by making the platform visible to the animals. Described in this unit is the use of the water maze to identify rats with age-related spatial learning and memory impairments. The efficacy of potential pharmacological treatments for alleviating these deficits is then evaluated. This assay provides a means for studying the neurobiology of spatial learning and memory, and to identify potential pharmacotherapies for treating memory-impaired humans. While the use of aged rats is described in this unit, the protocol can also be employed for compound screening with other rodent models that have spatial learning and memory impairments, such as transgenic mouse models of Alzheimer's disease.
Collapse
Affiliation(s)
- Gregory M Rose
- Center for Integrated Research in Cognitive & Neural Sciences and Department of Anatomy, Southern Illinois University, Carbondale, Illinois, USA
| | | |
Collapse
|
22
|
Link between cancer and Alzheimer disease via oxidative stress induced by nitric oxide-dependent mitochondrial DNA overproliferation and deletion. OXIDATIVE MEDICINE AND CELLULAR LONGEVITY 2013; 2013:962984. [PMID: 23691268 PMCID: PMC3649749 DOI: 10.1155/2013/962984] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/14/2012] [Accepted: 02/01/2013] [Indexed: 01/19/2023]
Abstract
Nitric oxide- (NO-) dependent oxidative stress results in mitochondrial ultrastructural alterations and DNA damage in cases of Alzheimer disease (AD). However, little is known about these pathways in human cancers, especially during the development as well as the progression of primary brain tumors and metastatic colorectal cancer. One of the key features of tumors is the deficiency in tissue energy that accompanies mitochondrial lesions and formation of the hypoxic smaller sized mitochondria with ultrastructural abnormalities. We speculate that mitochondrial involvement may play a significant role in the etiopathogenesis of cancer. Recent studies also demonstrate a potential link between AD and cancer, and anticancer drugs are being explored for the inhibition of AD-like pathology in transgenic mice. Severity of the cancer growth, metastasis, and brain pathology in AD (in animal models that mimic human AD) correlate with the degree of mitochondrial ultrastructural abnormalities. Recent advances in the cell-cycle reentry of the terminally differentiated neuronal cells indicate that NO-dependent mitochondrial abnormal activities and mitotic cell division are not the only important pathogenic factors in pathogenesis of cancer and AD, but open a new window for the development of novel treatment strategies for these devastating diseases.
Collapse
|
23
|
Chisholm NC, Kim T, Juraska JM. Males, but not females, lose tyrosine hydroxylase fibers in the medial prefrontal cortex and are impaired on a delayed alternation task during aging. Behav Brain Res 2013; 243:239-46. [PMID: 23327742 DOI: 10.1016/j.bbr.2013.01.009] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2012] [Revised: 01/02/2013] [Accepted: 01/08/2013] [Indexed: 02/08/2023]
Abstract
The structure of the prefrontal cortex (PFC) is particularly vulnerable to the effects of aging, and behaviors mediated by the PFC are impaired during aging in both humans and animals. In male rats, behavioral deficits have been correlated with a decrease in dopaminergic functioning. However, studies have found that anatomical changes associated with aging are sexually dimorphic, with males experiencing greater age-related loss than females. The present study investigated the effects of sex and aging on performance of a delayed alternation t-maze, a task mediated by the medial prefrontal cortex (mPFC), and on tyrosine hydroxylase (TH) immunoreactivity in this brain region using adult (7 months) and aged (21 months) male and female F344 rats. There was a sex by age interaction in performance of the delayed alternation task such that adult males performed better than aged males, but aged females were not different than adult females. Adult males performed better than adult females across all delays; however, this sex difference was reversed during aging and aged males performed worse than aged females. In addition, TH immunoreactivity decreased during aging in layers 2/3 in the male, but not female mPFC. Thus females were less sensitive to the effects of aging on the prefrontal dopaminergic system and on performance of a delayed alternation task. These effects may be due to decreases in testosterone in aging males, as well as the protective effects of ovarian hormones, which continue to be secreted after cessation of the estrous cycle in aging females.
Collapse
Affiliation(s)
- Nioka C Chisholm
- Department of Psychology, University of Illinois at Urbana-Champaign, Champaign, IL 61820, United States
| | | | | |
Collapse
|
24
|
Bayless DW, Darling JS, Stout WJ, Daniel JM. Sex differences in attentional processes in adult rats as measured by performance on the 5-choice serial reaction time task. Behav Brain Res 2012; 235:48-54. [DOI: 10.1016/j.bbr.2012.07.028] [Citation(s) in RCA: 41] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2012] [Revised: 07/10/2012] [Accepted: 07/16/2012] [Indexed: 10/28/2022]
|
25
|
Foster TC, Defazio RA, Bizon JL. Characterizing cognitive aging of spatial and contextual memory in animal models. Front Aging Neurosci 2012; 4:12. [PMID: 22988436 PMCID: PMC3439636 DOI: 10.3389/fnagi.2012.00012] [Citation(s) in RCA: 73] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2012] [Accepted: 05/15/2012] [Indexed: 11/30/2022] Open
Abstract
Episodic memory, especially memory for contextual or spatial information, is particularly vulnerable to age-related decline in humans and animal models of aging. The continuing improvement of virtual environment technology for testing humans signifies that widely used procedures employed in the animal literature for examining spatial memory could be developed for examining age-related cognitive decline in humans. The current review examines cross species considerations for implementing these tasks and translating findings across different levels of analysis. The specificity of brain systems as well as gaps in linking human and animal laboratory models is discussed.
Collapse
Affiliation(s)
- Thomas C Foster
- Department of Neuroscience, Evelyn F. and William L. McKnight Brain Institute, University of Florida Gainesville, FL, USA
| | | | | |
Collapse
|
26
|
Impact of the NGF maturation and degradation pathway on the cortical cholinergic system phenotype. J Neurosci 2012; 32:2002-12. [PMID: 22323714 DOI: 10.1523/jneurosci.1144-11.2012] [Citation(s) in RCA: 69] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
Cortical cholinergic atrophy plays a significant role in the cognitive loss seen with aging and in Alzheimer's disease (AD), but the mechanisms leading to it remain unresolved. Nerve growth factor (NGF) is the neurotrophin responsible for the phenotypic maintenance of basal forebrain cholinergic neurons in the mature and fully differentiated CNS. In consequence, its implication in cholinergic atrophy has been suspected; however, no mechanistic explanation has been provided. We have previously shown that the precursor of NGF (proNGF) is cleaved extracellularly by plasmin to form mature NGF (mNGF) and that mNGF is degraded by matrix metalloproteinase 9. Using cognitive-behavioral tests, Western blotting, and confocal and electron microscopy, this study demonstrates that a pharmacologically induced chronic failure in extracellular NGF maturation leads to a reduction in mNGF levels, proNGF accumulation, cholinergic degeneration, and cognitive impairment in rats. It also shows that inhibiting NGF degradation increases endogenous levels of the mature neurotrophin and increases the density of cortical cholinergic boutons. Together, the data point to a mechanism explaining cholinergic loss in neurodegenerative conditions such as AD and provide a potential therapeutic target for the protection or restoration of this CNS transmitter system in aging and AD.
Collapse
|
27
|
Williams CL. Sex differences in counting and timing. Front Integr Neurosci 2012; 5:88. [PMID: 22319476 PMCID: PMC3251826 DOI: 10.3389/fnint.2011.00088] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2011] [Accepted: 12/02/2011] [Indexed: 12/27/2022] Open
|
28
|
Age-related deficits in spatial memory and hippocampal spines in virgin, female Fischer 344 rats. Curr Gerontol Geriatr Res 2011; 2011:316386. [PMID: 21869884 PMCID: PMC3159305 DOI: 10.1155/2011/316386] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2011] [Accepted: 06/27/2011] [Indexed: 11/30/2022] Open
Abstract
Effects of aging on memory and brain morphology were examined in aged, 21-month-old, and young, 4-month-old, Fischer 344 female rats. Spatial memory was assessed using the object placement task, and dendritic spine density was determined on pyramidal neurons in the hippocampus following Golgi impregnation. Consistent with previous studies, aged females showed poorer object placement performance than young subjects. Young subjects significantly discriminated the location of objects with a 1.5-hour intertrial delay while aged subjects did not. Spine density of basal dendrites on CA1 pyramidal cells was 16% lower in the aged subjects as compared to the young subjects. No differences in spine density were found between young and aged subjects in basal dendrites of CA1 or in either dendritic field of CA3 pyramidal neurons. Thus, decreased hippocampal CA1 dendritic spine density in aged rats may contribute to poorer spatial memory as compared to young rats. The possibility that the neuroplastic changes observed in this study may pertain only to female subjects having had a specific set of life experiences is discussed. Different factors, such as reproductive status, diet, and handling may contribute to neuroplasticity of the brain during aging; however, this view requires further examination.
Collapse
|
29
|
Davis RL, Therrien BA, West BT. Cue conditions and wayfinding in older and younger women. Res Gerontol Nurs 2010; 1:252-63. [PMID: 20078000 DOI: 10.3928/19404921-20081001-06] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
This study examined how varying the salience and complexity of environmental cues affects place learning in older versus younger women. Place learning is a critical cognitive function for wayfinding in new or changed environments that becomes impaired with age in many people. Environments such as nursing homes and assisted living facilities typically have poorly differentiated environments. Environmental modifications that influence how older adults learn places more effectively are not known. It was hypothesized that salient cues (prominent and distinctive) are particularly important to place learning. The Computer-Generated Arena was used to test this hypothesis in 20 healthy older (age 65+) women and 6 healthy younger (ages 18 to 35) women. Analyses of the data showed differences in place learning with respect to cue salience, complexity, and age, with younger women being much more proficient in the place learning task and with the best overall learning in the salient and complex cue conditions.
Collapse
Affiliation(s)
- Rebecca L Davis
- Kirkhof College of Nursing, grand Valley State University, Grand Rapids, Michigan 49504, USA.
| | | | | |
Collapse
|
30
|
Niewiadomska G, Baksalerska-Pazera M, Riedel G. The septo-hippocampal system, learning and recovery of function. Prog Neuropsychopharmacol Biol Psychiatry 2009; 33:791-805. [PMID: 19389457 DOI: 10.1016/j.pnpbp.2009.03.039] [Citation(s) in RCA: 47] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/07/2009] [Accepted: 03/30/2009] [Indexed: 12/23/2022]
Abstract
We understand this review as an attempt to summarize recent advances in the understanding of cholinergic function in cognition. Such a role has been highlighted in the 1970s by the discovery that dementia patients have greatly reduced cholinergic activity in cortex and hippocampus. A brief anatomical description of the major cholinergic pathways focuses on the basal forebrain and its projections to cortex and hippocampus. From this distinction, compelling evidence suggests that the basal forebrain --> cortex projection regulates the excitability of principal cortical neurons and is thereby critically involved in attention, stimulus detection and memory function, although the biological conditions for these functions are still debated. Similar uncertainties remain for the septo-hippocampal cholinergic system. Although initial lesions of the septum caused memory deficits reminiscent of hippocampal ablations, recent and more refined neurotoxic lesion studies which spared non-cholinergic cells of the basal forebrain failed to confirm these memory impairments in experimental animals despite a near total loss of cholinergic labeling. Yet, a decline in cholinergic markers in aging and dementia still stands as the most central piece of evidence for a link between the cholinergic system and cognition and appear to provide valuable targets for therapeutic approaches.
Collapse
|
31
|
Abstract
Individuals create cognitive maps based on relationships between cues in the environment. Older individuals are often impaired in wayfinding, especially in environments that lack distinctive features. This study examines how working memory ability in older women is related to wayfinding performance in the presence of salient (distinctive, prominent) or nonsalient cues. The degree of salient cue complexity is also examined, thus leading to the hypothesis that salient, complex cues are important in wayfinding and that working memory capacity is related to wayfinding performance. The virtual computer-generated arena is used to test this hypothesis in 20 healthy older women in three different environmental cue conditions varying in salience and complexity. Data analyses indicate that older women perform best in salient cue conditions. A greater working memory capacity is related to improved performance in the nonsalient cue condition. These findings offer preliminary evidence that cue salience is especially important in wayfinding.
Collapse
|
32
|
Zou XH, Li HM, Wang S, Leski M, Yao YC, Yang XD, Huang QJ, Chen GQ. The effect of 3-hydroxybutyrate methyl ester on learning and memory in mice. Biomaterials 2009; 30:1532-41. [PMID: 19111894 DOI: 10.1016/j.biomaterials.2008.12.012] [Citation(s) in RCA: 51] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2008] [Accepted: 12/04/2008] [Indexed: 01/25/2023]
Abstract
Learning and memory requires energy-demanding cellular processes and can be enhanced when the brain is supplemented with metabolic substrates. In this study, we found that neuroglial cell metabolic activity was significantly elevated when cultured in the presence of polyhydroxybutyrate (PHB) degradation product 3-hydroxybutyrate (3-HB) and derivatives. We demonstrated that the receptor for 3-HB, namely, protein upregulated in macrophages by IFN-gamma (PUMA-G), was expressed in brain and upregulated in mice treated with 3-hydroxybutyrate methyl ester (3-HBME). We also affirmed increased expression of connexin 36 protein and phosphorylated ERK2 (extracellular signal-regulated kinase 2) in brain tissues following 3-HBME treatment, although these differences were not statistically significant. Mice treated with 3-HBME performed significantly (p<0.05) better in the Morris water maze than either the negative controls (no treatment) or positive controls (acetyl-l-carnitine treatment). Moreover, we found that 3-HBME enhanced gap junctional intercellular communication between neurons. Thus, 3-HB and derivatives enhance learning and memory, possibly through a signaling pathway requiring PUMA-G that increases protein synthesis and gap junctional intercellular communication.
Collapse
Affiliation(s)
- Xiang-Hui Zou
- Multidisciplinary Research Center, Shantou University, Shantou, Guangdong, China
| | | | | | | | | | | | | | | |
Collapse
|
33
|
Guzmán CB, Graham KA, Grace LA, Moore AH. Sex-dependent effect of cyclooxygenase-2 inhibition on mouse spatial memory. Behav Brain Res 2009; 199:355-9. [PMID: 19162088 DOI: 10.1016/j.bbr.2009.01.005] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2008] [Revised: 11/24/2008] [Accepted: 01/04/2009] [Indexed: 11/30/2022]
Abstract
Cyclooxygenase (COX)-2 is constitutively expressed in neurons of the hippocampus and neocortex. Therefore, non-steroidal anti-inflammatory drugs (NSAIDs) targeting inflammation-induced COX-2 in the periphery and the central nervous system may also affect cognitive function mediated by basal COX-2 activity. We report that systemic administration of the selective COX-2 inhibitor NS-398 6h prior to behavioral assessment does not influence spatial acquisition or retention in male C57BL/6J mice. However, we observed impaired spatial retention in female mice treated with NS-398, suggesting a sex-dependent role of COX-2 in spatial memory of mice.
Collapse
Affiliation(s)
- Cristina B Guzmán
- Department of Biology, Santa Clara University, 500 El Camino Real, Santa Clara, CA 95053, United States
| | | | | | | |
Collapse
|
34
|
Effects of age and anxiety on learning and memory. Behav Brain Res 2008; 195:147-52. [DOI: 10.1016/j.bbr.2008.05.023] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2007] [Revised: 05/30/2008] [Accepted: 05/30/2008] [Indexed: 11/21/2022]
|
35
|
Fragkouli A, Pachnis V, Stylianopoulou F. Sex differences in water maze performance and cortical neurotrophin levels of LHX7 null mutant mice. Neuroscience 2008; 158:1224-33. [PMID: 19095044 DOI: 10.1016/j.neuroscience.2008.11.026] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2008] [Revised: 10/20/2008] [Accepted: 11/13/2008] [Indexed: 01/08/2023]
Abstract
Mice lacking both alleles of the LIM-homeobox gene Lhx7 display dramatically reduced number of forebrain cholinergic neurons. Given the fact that sex differences are consistently observed in forebrain cholinergic function, in the present study we investigated whether the absence of LHX7 differentially affects water maze performance in the two sexes. Herein we demonstrate that LHX7 null mutants display a sex-dependent impairment in water maze, with females appearing more affected than males. Moreover, neurotrophin assessment revealed a compensatory increase of brain-derived neurotrophic factor and neurotrophin 3 in the neocortex of both male and female mutants and an increase of nerve growth factor levels only in the females. Nevertheless, the compensatory increase of cortical neurotrophin levels did not restore cognitive abilities of Lhx7 homozygous mutants. Finally, our analysis revealed that cortical neurotrophin levels correlate negatively with water maze proficiency, indicating that there is an optimal neurotrophin level for successful cognitive performance.
Collapse
Affiliation(s)
- A Fragkouli
- Department of Basic Sciences, University of Athens, 11527 Athens, Greece
| | | | | |
Collapse
|
36
|
Yates MA, Markham JA, Anderson SE, Morris JR, Juraska JM. Regional variability in age-related loss of neurons from the primary visual cortex and medial prefrontal cortex of male and female rats. Brain Res 2008; 1218:1-12. [PMID: 18513705 DOI: 10.1016/j.brainres.2008.04.055] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2007] [Revised: 11/16/2007] [Accepted: 04/23/2008] [Indexed: 11/17/2022]
Abstract
During aging, changes in the structure of the cerebral cortex of the rat have been seen, but potential changes in neuron number remain largely unexplored. In the present study, stereological methods were used to examine neuron number in the medial prefrontal cortex and primary visual cortex of young adult (85-90 days of age) and aged (19-22 months old) male and female rats in order to investigate any age-related losses. Possible sex differences in aging were also examined since sexually dimorphic patterns of aging have been seen in other measures. An age-related loss of neurons (18-20%), which was mirrored in volume losses, was found to occur in the primary visual cortex in both sexes in all layers except IV. Males, but not females, also lost neurons (15%) from layer V/VI of the ventral medial prefrontal cortex and showed an overall decrease in volume of this region. In contrast, dorsal medial prefrontal cortex showed no age-related changes. The effects of aging clearly differ among regions of the rat brain and to some degree, between the sexes.
Collapse
Affiliation(s)
- M A Yates
- Psychology Department, University of Illinois Urbana-Champaign, Champaign, IL 61820, USA
| | | | | | | | | |
Collapse
|
37
|
Markham JA, Juraska JM. Social recognition memory: influence of age, sex, and ovarian hormonal status. Physiol Behav 2007; 92:881-8. [PMID: 17673265 PMCID: PMC2151760 DOI: 10.1016/j.physbeh.2007.06.020] [Citation(s) in RCA: 61] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2007] [Revised: 05/29/2007] [Accepted: 06/25/2007] [Indexed: 11/19/2022]
Abstract
Social recognition memory underlies many forms of rodent interaction and can be easily tested in the laboratory. Sex differences in aspects of this memory have been reported among young adults, and some studies indicate an age-related decline among male rats. In contrast, neither the impact of natural fluctuations in ovarian hormones nor the performance of aged female rats on social recognition memory has been previously evaluated. In experiments 1 and 2, the social recognition memory of young adult female Long-Evans rats (age 3-5 months) was compared during proestrus and estrus, and performance was found to be stable across estrous cycle phases. In experiment 3, the social recognition memory of young adults as compared to aged (16.5-19.5 months) rats was tested using the social discrimination procedure, following delays of 15, 45, 90 or 120 min. The estropausal status of aged female rats was tracked during the experiment but was not found to influence memory ability. Males of both ages investigated juveniles (both novel and familiar) more than did females, although despite this difference, both sexes demonstrated robust memory. Interestingly, only young adult females were capable of demonstrating memory following the longest delay. Collectively, our findings indicate that the pattern of age-related changes in social recognition memory is subtle and that aging does not greatly alter the behavioral sex differences observed among young adults.
Collapse
Affiliation(s)
- Julie A Markham
- Department of Psychology, University of Illinois at Urbana-Champaign, Urbana, Illinois 61801, USA.
| | | |
Collapse
|
38
|
Murchison D, Griffith WH. Calcium buffering systems and calcium signaling in aged rat basal forebrain neurons. Aging Cell 2007; 6:297-305. [PMID: 17517040 PMCID: PMC2810842 DOI: 10.1111/j.1474-9726.2007.00293.x] [Citation(s) in RCA: 64] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022] Open
Abstract
Disturbances of neuronal Ca2+ homeostasis are considered to be important determinants of age-related cognitive impairment. Cholinergic neurons of the basal forebrain (BF) are principal targets of decline associated with aging and dementia. During the last several years, we have attempted to link these concepts in a rat model of 'normal' aging. In this review, we will describe some changes that we have observed in Ca2+ signaling of aged BF neurons and the reversal of one of these changes by dietary caloric restriction. Our evidence supports a scenario in which subtle changes in the properties of voltage-gated Ca2+ channels result in increased Ca2+ influx during aging. This increased Ca2+, in turn, triggers an increase in rapid Ca2+ buffering in the somatic compartment of aged BF neurons. However, this nominal 'compensation', along with other changes in Ca2+ handling machinery (notably mitochondria) alters the Ca2+ signal with age in a way that is dependent on the magnitude of the Ca2+ load. By combining whole-cell patch clamp electrophysiology, ratiometric Ca2+-sensitive microfluorimetry and single-cell reverse transcription-polymerase chain reaction, we have determined that age-related rapid buffering changes are present in identified cholinergic BF neurons and that these changes can be prevented by a caloric restriction dietary regimen. Because caloric restriction extends lifespan and retards the progression of age-related dysfunction, these findings suggest that increased Ca2+ buffering in cholinergic neurons may be relevant to cognitive decline during normal aging. Importantly, calcium homeostatic mechanisms of BF cholinergic neurons are amenable to dietary interventions that could promote cognitive health during aging.
Collapse
Affiliation(s)
- David Murchison
- Department of Neuroscience and Experimental Therapeutics, College of Medicine, Texas A&M University System Health Science Center, College Station, TX 77843-1114, USA
| | | |
Collapse
|
39
|
LaSarge CL, Montgomery KS, Tucker C, Slaton GS, Griffith WH, Setlow B, Bizon JL. Deficits across multiple cognitive domains in a subset of aged Fischer 344 rats. Neurobiol Aging 2007; 28:928-36. [PMID: 16806587 DOI: 10.1016/j.neurobiolaging.2006.04.010] [Citation(s) in RCA: 56] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/31/2005] [Revised: 04/03/2006] [Accepted: 04/30/2006] [Indexed: 11/21/2022]
Abstract
Rodent models of cognitive aging routinely use spatial performance on the water maze to characterize medial temporal lobe integrity. Water maze performance is dependent upon this system and, as in the aged human population, individual differences in learning abilities are reliably observed among spatially characterized aged rats. However, unlike human aging in which cognitive deficits rarely occur in isolation, few non-spatial learning deficits have been identified in association with spatial impairment among aged rats. In this study, a subset of male aged Fischer 344 rats was impaired both in water maze and odor discrimination tasks, whereas other aged cohorts performed on par with young adult rats in both settings. The odor discrimination learning deficits were reliable across multiple problems. Moreover, these deficits were not a consequence of anosmia and were specific to olfactory learning, as cognitively impaired aged rats performed normally on an analogous non-olfactory discrimination task. These are among the first data to describe an aging model in which individual variability among aged rat cognition occurs across two independent behavioral domains.
Collapse
Affiliation(s)
- Candi L LaSarge
- Department of Psychology, Texas A&M University, College Station, TX 77843-4235, United States
| | | | | | | | | | | | | |
Collapse
|
40
|
Martin DM, Wittert G, Burns NR. Gonadal steroids and visuo-spatial abilities in adult males: implications for generalized age-related cognitive decline. Aging Male 2007; 10:17-29. [PMID: 17454979 DOI: 10.1080/13685530601183537] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/23/2022] Open
Abstract
The relationship between the gonadal steroids, testosterone and estrogen, and individual and group differences in performance on some cognitive tasks remains unclear but sex differences favoring males on some tests of visuo-spatial ability are large and robust. This aim of this review is to assess evidence for both organizational and activational effects of gonadal steroids as the principle cause of sex difference in visuo-spatial ability. Additionally, the implications of this relationship are discussed in the context of decreasing levels of gonadal steroids in aging males and psychological theories of generalized age-related cognitive decline. Based upon human and non-human research gonadal steroids have organizational effects on visuo-spatial ability in adulthood. Activational effects of gonadal steroids on visuo-spatial ability appear most dominant in older men and are necessary for maintaining optimal visuo-spatial ability; randomized clinical trials show that testosterone supplementation improves performance. Additionally, decreasing gonadal steroid levels in aging males may contribute to generalized age-related cognitive decline. Future supplementation studies in men should attempt to control for constituent abilities related to visuo-spatial task performance, and investigate interactions between dosage levels and baseline gonadal status. Further future animal research is required to investigate changes in gonadal steroid levels and their relationship to neurotransmitter systems, neural plasticity, and behavioral correlates.
Collapse
Affiliation(s)
- Donel M Martin
- School of Psychology, University of Adelaide, South Australia, Australia.
| | | | | |
Collapse
|
41
|
Sutcliffe JS, Marshall KM, Neill JC. Influence of gender on working and spatial memory in the novel object recognition task in the rat. Behav Brain Res 2007; 177:117-25. [PMID: 17123641 DOI: 10.1016/j.bbr.2006.10.029] [Citation(s) in RCA: 171] [Impact Index Per Article: 10.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2006] [Revised: 10/26/2006] [Accepted: 10/30/2006] [Indexed: 10/23/2022]
Abstract
Gender differences in many behavioural tasks have been observed in both humans and laboratory animals. The novel object recognition (NOR) task is increasingly used to investigate drug effects on working memory processes, although, the influence of sexually dimorphic behaviours have not yet been evaluated. In addition, the role of natural fluctuations in the sex steroids during the oestrous cycle has received little attention during object recognition tasks. Therefore, the aim of the current study was to investigate the influence of gender and oestrous cycle phase on working and spatial memory using the NOR task. Animals were tested in the NOR task and the spatial NOR task. Male and female rats completed an acquisition trial followed by an inter-trial interval of a specified length, then a final retention trial. Vaginal cytology enabled the influence of oestrous cycle phase to be determined in both the NOR and spatial NOR, each animal was tested during one phase of their regular oestrous cycle only. It was found that female rats performed significantly better than male rats in the standard NOR paradigm (p<0.05 compared to no significance (NS) at 3h, respectively), while male rats showed improved memory in the spatial NOR paradigm compared with female rats (p<0.05 compared to NS at 3h, respectively). There was no influence of phase of oestrous cycle on the NOR task, however, during the spatial NOR there was a significant improvement in ability when oestrogen and progesterone levels have been shown to be at their lowest (i.e. p<0.05 during oestrous compared to NS at other stages). In conclusion, it is clear that gonadal hormones can influence components of memory and gender is an important consideration in experimental design.
Collapse
Affiliation(s)
- J S Sutcliffe
- School of Pharmacy, University of Bradford, Bradford, West Yorkshire BD7 1DP, UK
| | | | | |
Collapse
|
42
|
Bowman RE, Maclusky NJ, Diaz SE, Zrull MC, Luine VN. Aged rats: Sex differences and responses to chronic stress. Brain Res 2006; 1126:156-66. [PMID: 16919611 DOI: 10.1016/j.brainres.2006.07.047] [Citation(s) in RCA: 70] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2006] [Revised: 07/02/2006] [Accepted: 07/18/2006] [Indexed: 11/15/2022]
Abstract
Cognitive, as well as physiological, sex differences exist in young adult rats under both basal conditions and following chronic stress; however, few studies have examined whether sex differences remain in aged subjects and whether responses to stress are altered. We compared aged male and female Fischer 344 rats (21.5 months at testing) without stress and when given 21 days of restraint for 6 h/day on locomotion, anxiety-related behaviors, object recognition (non-spatial memory), object placement (spatial memory), body weight and serum steroid hormone levels. Control (unstressed) females had lower levels of estradiol and testosterone and higher corticosterone than males, and stress had no lasting effect on hormone concentrations. Females weighed less than males and showed less weight loss with stress. Locomotion measures on an open field were similar in the sexes and unaffected by stress. Anxiety-related behavior measures on the field showed that males were generally more anxious and that stress increased male, but decreased, female anxiety-related behaviors. In memory testing, exploration of objects was not different between the sexes, with or without stress, while stress increased exploration in both sexes during object recognition trials. Both males and females, regardless of treatment, discriminated between old and new objects at short, but not long, inter-trial delays. The typical advantage of young males for spatial memory performance was not observed in aged subjects on the object placement tasks. Stress-dependent enhancements in females and impairments in males for object placement are reported for young rats, but in aged rats, neither sex was altered by stress. Current data suggest that aging is associated with changes in the pattern of sex differences present in young adult rats in some behaviors and in the behavioral responses to stress.
Collapse
Affiliation(s)
- Rachel E Bowman
- Department of Psychology, Sacred Heart University, 5151 Park Avenue, Fairfield, CT 06825, USA.
| | | | | | | | | |
Collapse
|
43
|
Niewiadomska G, Baksalerska-Pazera M, Gasiorowska A, Mietelska A. Nerve Growth Factor Differentially Affects Spatial and Recognition Memory in Aged Rats. Neurochem Res 2006; 31:1481-90. [PMID: 17111224 DOI: 10.1007/s11064-006-9209-5] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2006] [Accepted: 10/20/2006] [Indexed: 10/23/2022]
Abstract
In rats, object discrimination depends on the integrity of the cholinergic system, thus it could be expected that nerve growth factor (NGF) can improve the behavior in aged subjects. The interactive effect of age and cholinergic improvement was assessed behaviorally in young and aged rats. Animals were injected by infusion of NGF into the lateral ventricles and they were tested in two behavioral tasks: an object-location and an object-recognition task. Spatial and recognition memory were assessed in an open field containing five different objects. Rats were submitted to six consecutive sessions. Both age-groups showed comparable habituation of exploratory response in Session 1-4. Discrimination index (DI) was calculated to assess responses to spatial change in Session 5 and object change in Session 6. Control young and aged rats were able to discriminate between familiar and novel object, however DI was lower in aged rats. Treatment with NGF induced decline of object discrimination in both age-groups. Different results were obtained in spatial displacement test. NGF was able to improve spatial memory in aged rats, but had no effect in young controls. These data confer on NGF potential role in improving spatial but not episodic memory in aged rats.
Collapse
Affiliation(s)
- G Niewiadomska
- Department of Neurophysiology, Nencki Institute for Experimental Biology, 02-093, Warsaw, Poland.
| | | | | | | |
Collapse
|
44
|
Williams BJ, Bimonte-Nelson HA, Granholm-Bentley AC. ERK-mediated NGF signaling in the rat septo-hippocampal pathway diminishes with age. Psychopharmacology (Berl) 2006; 188:605-18. [PMID: 16915384 DOI: 10.1007/s00213-006-0477-1] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/01/2006] [Accepted: 06/10/2006] [Indexed: 01/01/2023]
Abstract
RATIONALE Degeneration of basal forebrain cholinergic neurons (BFCNs) plays an important role in aging and Alzheimer's disease (AD) pathology. This degeneration may be a result of disrupted nerve growth factor (NGF) signaling. Aged rats have memory deficits, BFCN degeneration, and disrupted NGF signaling. OBJECTIVE In this study we identify a rapid NGF signaling pathway in BFCNs and the second messenger system associated with that signaling. We also identify age-dependent alterations in this signaling pathway. MATERIALS AND METHODS After cognitive assessment using the Morris water maze, rats were given an intra-hippocampal NGF injection. Basal forebrain immunohistochemical analysis, confocal microscopy, and inhibitor studies were performed. RESULTS An increase in immunoreactivity for the NGF receptor TrkA was found in cell bodies of BFCNs 15 min and 1 h post-NGF injection. Immunohistochemistry studies with phospho-ERK and phospho-AKT antibodies showed that this rapid signaling occurred through MAP kinase, but not PI-3 kinase pathways. MAPK inhibitor studies attenuated the NGF-induced effects. Both TrkA and phospho-ERK (extracellular signal-regulated kinase) immunoreactivities were diminished in aged rats and phospho-ERK immunoreactivity-correlated with aged rat performance in the Morris water maze. CONCLUSIONS Rapid NGF signaling likely occurs in the rat CNS through the MAPK signaling pathway. This rapid signaling pathway is diminished in aged rats compared to young ones and may contribute to memory deficits observed in aged rats. As cholinergic degeneration coupled with altered levels of NGF and TrkA receptors are also seen in human aging and AD, ERK-related dysfunction may be relevant in human conditions as well.
Collapse
Affiliation(s)
- Brice J Williams
- Department of Neurosciences, Center on Aging, Charleston, SC 29425, USA
| | | | | |
Collapse
|
45
|
Williams BJ, Eriksdotter-Jonhagen M, Granholm AC. Nerve growth factor in treatment and pathogenesis of Alzheimer's disease. Prog Neurobiol 2006; 80:114-28. [PMID: 17084014 DOI: 10.1016/j.pneurobio.2006.09.001] [Citation(s) in RCA: 62] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2006] [Accepted: 09/05/2006] [Indexed: 10/24/2022]
Abstract
The etiology of Alzheimer's disease (AD) is still unknown. In addition, this terrible neurodegenerative disease will increase exponentially over the next two decades due to longer lifespan and an aging "baby-boomer" generation. All treatments currently approved for AD have moderate efficacy in slowing the rate of cognitive decline in patients, and no efficacy in halting progression of the disease. Hence, there is an urgent need for new drug targets and delivery methods to slow or reverse the progression of AD. One molecule that has received much attention in its potential therapeutic role in AD is nerve growth factor (NGF). This review will demonstrate data from humans and animals which promote NGF as a potential therapeutic target by (1) outlining the hypothesis behind using NGF for the treatment of AD, (2) reviewing both the normal and AD altered signaling pathways and effects of NGF in the central nervous system (CNS), and (3) examining the results of NGF treatment obtained from animal models of AD and AD patients.
Collapse
Affiliation(s)
- Brice J Williams
- Department of Neurosciences and the Center on Aging, Medical University of South Carolina, 173 Ashley Ave BSB 403, Charleston, SC 29425, United States
| | | | | |
Collapse
|
46
|
Abstract
Stress exposure, depending on intensity and duration, elicits adaptive or maladaptive physiological changes. The same general pattern of advantageous versus deleterious stress effects appears to exist for some cognitive functions, particularly spatial learning and memory performance. This article reviews sex differences in response to stress on a variety of spatial tasks. In general, females are more resistant than males to stress-induced impairments on spatial tasks, including the radial arm maze and object placement. In young adulthood, chronic stress (restraint, 6 h per day for 21 days) impairs male performance on both tasks but leads to behavioural enhancements in females. Furthermore, these sex-dependent stress effects are influenced by both organisational and activational oestrogenic effects. Additionally, sex-specific stress responses vary depending on developmental age at the time of stress exposure. Male behavioural stress responses appear fixed across the lifespan (i.e. stress-induced cognitive impairments) whereas female stress responses appear more variable (i.e. stress-induced enhancements observed in young adulthood are different in response to prenatal stress and diminished following stress exposure at old age). These findings underscore the point that many effects obtained in males cannot be generalised to females and highlight the need to investigate the stress response at different ages and in both sexes.
Collapse
Affiliation(s)
- R E Bowman
- Department of Psychology, Sacred Heart University, Fairfield, CT 06825, USA.
| |
Collapse
|
47
|
Markham JA, McKian KP, Stroup TS, Juraska JM. Sexually dimorphic aging of dendritic morphology in CA1 of hippocampus. Hippocampus 2005; 15:97-103. [PMID: 15390161 DOI: 10.1002/hipo.20034] [Citation(s) in RCA: 82] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
During aging, rats of both sexes experience a decline in performance on hippocampal-dependent tasks. Investigations into the neuroanatomical correlates of this functional decline have been conducted almost exclusively in male subjects. In the present study, dendritic spine density in stratum radiatum and complexity of the entire apical dendritic tree were quantified using Golgi-Cox-stained tissue in young (3-5 months) and aged (19-22 months) rats of both sexes. Because both cognitive decline and hippocampal morphology may be influenced by ovarian hormonal state, young adult females were examined during either proestrus or estrus, and aged females were examined in one of two reproductively senescent states: persistent estrus or persistent diestrus. A sex difference in dendritic branching of CA1 pyramidal cells was found among young adults. However, this difference disappeared during aging, due to a reduction in branching with age for males but not for females. Spine density was not influenced by age or sex, nor did ovarian hormone status influence either measure. These results are consistent with our previous findings in the rat medial prefrontal cortex and primary motor cortex and with the human literature, which indicate that age-related atrophy of cognitive brain regions is more severe for males than females.
Collapse
Affiliation(s)
- J A Markham
- Department of Psychology, University of Illinois at Urbana-Champaign, Champaign, Illinois 61820, USA
| | | | | | | |
Collapse
|
48
|
Masuda J, Mitsushima D, Funabashi T, Kimura F. Sex and housing conditions affect the 24-h acetylcholine release profile in the hippocampus in rats. Neuroscience 2005; 132:537-42. [PMID: 15802204 DOI: 10.1016/j.neuroscience.2005.01.010] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 01/12/2005] [Indexed: 11/21/2022]
Abstract
To examine the sex difference in the 24-h profile of the acetylcholine (ACh) release in the hippocampus, in addition to the effects of housing conditions on this profile, we performed an in vivo microdialysis study in intact male and cycling female rats that had been living in large (diameter=35 cm) or small (diameter=19 cm) cylindrical cages. Each rat was individually housed in a cage for 4 days. On the day of the experiment, the dialysate was collected from the dorsal hippocampus at 20-min intervals and sequential blood samples were simultaneously obtained at 2-h intervals, under the freely moving condition for more than 24 h. ACh in the dialysates was measured by the high performance liquid chromatography system, while the corticosterone concentration in the serum was measured by radiostereoassay. Although the ACh release showed a clear daily rhythm in both sexes of rats, the amount of ACh released in female rats was significantly lower than that in males. Furthermore, the housing in the small cage significantly attenuated the ACh release during the dark phase in male rats, but not in female rats. Conversely, the serum corticosterone concentration showed a clear daily rhythm and the mean concentration of serum corticosterone in female rats was significantly higher than that in male rats. Housing in the small cage did not affect the corticosterone rhythm in either sex. These results reveal a sex difference in the 24-h profile of the ACh release, which suggests vulnerability of the cholinergic system in male rats depending on its housing conditions.
Collapse
Affiliation(s)
- J Masuda
- Department of Neuroendocrinology, Yokohama City University Graduate School of Medicine, 3-9 Fukuura, Kanazawaku, Yokohama, 236-0004, Japan
| | | | | | | |
Collapse
|
49
|
Lacreuse A, Kim CB, Rosene DL, Killiany RJ, Moss MB, Moore TL, Chennareddi L, Herndon JG. Sex, Age, and Training Modulate Spatial Memory in the Rhesus Monkey (Macaca mulatta). Behav Neurosci 2005; 119:118-26. [PMID: 15727518 DOI: 10.1037/0735-7044.119.1.118] [Citation(s) in RCA: 46] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
The authors tested 90 rhesus monkeys (Macaca mulatta) on a task of spatial memory, the spatial Delayed Recognition Span Test. The results showed that performance declined significantly with age, males had greater scores than females, and the rate of apparent decline with age was greater in males than in females. Both working and reference memory declined with age, but only working memory showed sex differences. The authors compared these data with that of 22 monkeys who were trained on a simpler version of the task before formal testing. Training had no effect on males but dramatically improved working memory in young females. The results confirm a male advantage in spatial working memory at a young age and confirm a greater decline with age in males than in females. It is important to note that prior training completely reverses the deficits of young females.
Collapse
Affiliation(s)
- Agnès Lacreuse
- Yerkes National Primate Research Center, Emory University, Atlanta, GA, 30322 USA.
| | | | | | | | | | | | | | | |
Collapse
|
50
|
Brown RW, Flanigan TJ, Thompson KN, Thacker SK, Schaefer TL, Williams MT. Neonatal quinpirole treatment impairs Morris water task performance in early postweanling rats: relationship to increases in corticosterone and decreases in neurotrophic factors. Biol Psychiatry 2004; 56:161-8. [PMID: 15271584 DOI: 10.1016/j.biopsych.2004.05.003] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/12/2003] [Revised: 04/15/2004] [Accepted: 05/04/2004] [Indexed: 11/22/2022]
Abstract
BACKGROUND Past studies from this laboratory have shown that quinpirole administration from postnatal day (P) 1-21 produces persistent supersensitization of the dopamine D2 receptor that persists throughout the animal's lifetime. METHODS In Experiment 1, both male and female rats were treated with quinpirole or saline from P1-21 and tested on the place and match-to-place versions of the Morris water task (MWT) from P22-28. In Experiment 2, both male and female rats were administered either acute or chronic injections of quinpirole (1 mg/kg) or saline beginning on P1 until analysis for corticosterone (CORT) on P7, 14, or 21. RESULTS Neonatal quinpirole treatment produced deficits on both versions of the MWT compared with saline control. One day after behavioral testing, brain tissue was harvested, and the hippocampus was analyzed for nerve growth factor (NGF) and brain-derived nerve growth factor (BDNF); NGF was found to be significantly decreased by neonatal quinpirole treatment. Acute or chronic quinpirole treatment on P14 produced a larger increase in CORT than controls and produced larger increases in CORT than control rats on P21. CONCLUSIONS These results demonstrate that neonatal quinpirole treatment produces cognitive deficits that could be related to decreases in hippocampal NGF and increases in CORT, resulting in abnormalities in hippocampal development.
Collapse
Affiliation(s)
- Russell W Brown
- Department of Psychology, Quillen College of Medicine, East Tennessee State University, Johnson City, Tennessee, USA.
| | | | | | | | | | | |
Collapse
|