This project developed out of studies on calcium (Ca2+) regulation in age-related neurodegeneration and examination of Ca2+ dependent synaptic plasticity as a neural mechanism for memory. Previous electrophysiological studies in this project found an age-related shift in the balance of synaptic plasticity, long-term potentiation (LTP) and long-term depression (LTD), favoring LTD. The shift in the LTD/LTP balance was associated with Ca2+-dysregulation involving L-type Ca2+ channels and the activity of protein phosphatases and kinases involved in synaptic plasticity. From this work we have proposed the hypothesis that a Ca2+ dependent enhancement of LTD relative to LTP is a major factor in synaptic and cognitive impairment with age. Here we will focus on two main goals: 1) to test the hypothesized link between the LTD/LTP shift and cognitive decline in aging, and 2) to unravel the cellular mechanistic pathways through which age-related altered Ca2+ regulation is linked to the LTD/LTP shift.
Specific aims are designed to determine if the age-related shift in LTD/LTP is associated with cognitive decline and determine whether procedures to counteract shift in LTD/LIP also counteracts the memory impairment in aged animals.
Other aims will determine whether intracellular Ca2+ stores contribute to altered synaptic plasticity during aging, and identify intermediate linking steps between Ca2+ dysregulation and altered synaptic function (e.g. calcineurin). We believe that the results of our experiments will add significantly to our knowledge of mechanisms for regulation of synaptic function across the life span and provide a basis for understanding the role of synaptic plasticity in cognitive function.

Agency
National Institute of Health (NIH)
Institute
National Institute on Aging (NIA)
Type
Research Project (R01)
Project #
2R01AG014979-04
Application #
6333660
Study Section
Special Emphasis Panel (ZRG1-IFCN-5 (02))
Program Officer
Wise, Bradley C
Project Start
1997-12-01
Project End
2006-06-30
Budget Start
2001-07-01
Budget End
2002-06-30
Support Year
4
Fiscal Year
2001
Total Cost
$217,200
Indirect Cost
Name
University of Kentucky
Department
Pharmacology
Type
Schools of Medicine
DUNS #
832127323
City
Lexington
State
KY
Country
United States
Zip Code
40506
Kumar, Ashok; Foster, Thomas C (2018) Alteration in NMDA Receptor Mediated Glutamatergic Neurotransmission in the Hippocampus During Senescence. Neurochem Res :
Kumar, Ashok; Rani, Asha; Scheinert, Rachel B et al. (2018) Nonsteroidal anti-inflammatory drug, indomethacin improves spatial memory and NMDA receptor function in aged animals. Neurobiol Aging 70:184-193
Kumar, Ashok; Bean, Linda A; Rani, Asha et al. (2015) Contribution of estrogen receptor subtypes, ER?, ER?, and GPER1 in rapid estradiol-mediated enhancement of hippocampal synaptic transmission in mice. Hippocampus 25:1556-66
Scheinert, Rachel B; Asokan, Aditya; Rani, Asha et al. (2015) Some hormone, cytokine and chemokine levels that change across lifespan vary by cognitive status in male Fischer 344 rats. Brain Behav Immun 49:216-32
Speisman, Rachel B; Kumar, Ashok; Rani, Asha et al. (2013) Daily exercise improves memory, stimulates hippocampal neurogenesis and modulates immune and neuroimmune cytokines in aging rats. Brain Behav Immun 28:25-43
Speisman, Rachel B; Kumar, Ashok; Rani, Asha et al. (2013) Environmental enrichment restores neurogenesis and rapid acquisition in aged rats. Neurobiol Aging 34:263-74
Boye, Sanford L; Peshenko, Igor V; Huang, Wei Chieh et al. (2013) AAV-mediated gene therapy in the guanylate cyclase (RetGC1/RetGC2) double knockout mouse model of Leber congenital amaurosis. Hum Gene Ther 24:189-202
Brim, B L; Haskell, R; Awedikian, R et al. (2013) Memory in aged mice is rescued by enhanced expression of the GluN2B subunit of the NMDA receptor. Behav Brain Res 238:211-26
Han, Xiaoxia; Aenlle, Kristina K; Bean, Linda A et al. (2013) Role of estrogen receptor ýý and ýý in preserving hippocampal function during aging. J Neurosci 33:2671-83
Foster, Thomas C; Defazio, R A; Bizon, Jennifer L (2012) Characterizing cognitive aging of spatial and contextual memory in animal models. Front Aging Neurosci 4:12

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