In neurodegenerative disorders such as Alzheimers, Parkinsons and Huntingtons diseases, neurons may die by a form of programmed cell death called apoptosis. A major effort in the Cellular and Molecular Neurosciences section of the Laboratory of Neurosciences is aimed at establishing what triggers apoptosis in neurodegenerative disorders and how neuronal degeneration might be prevented by targeting specific molecular events in the process of apoptosis. We have found that a protein called p53 is involved in the death of neurons in experimental models of Alzheimers, Parkinsons and Huntingtons diseases. Novel specific inhibitors of p53 were developed and several lead agents were shown to be effective in animal models of stroke and Parkinsons disease. In other studies we established important roles for potassium ion fluxes in the pathogenesis of neuronal degeneration in models of stroke. A drug called diazoxide that opens mitochondrial potassium channels was neuronprotective in models of stroke. In studies of the mechanism by which neurons die in Alzheimers disease we have found that damage to DNA causes the neurons to undergo an abortive attempt to re-enter the cell cycle resulting in activation of the ATM kinase and p53 which trigger apoptosis. Our studies of telomere function in neurons have revealed roles for several telomere-associated proteins in preventing apoptosis. Damage to mitochondrial DNA may also trigger apoptosis, but a DNA repair protein called OGG1 can protect neurons from dying in models of neurodegenerative disorders. In addition, we have identified a mitochondrial uncoupling protein (UCP4) that can protect neurons in models relevant to stroke and Alzheimers disease by a mechanism involving suppression of oxidative stress and stabilization of cellular calcium homeostasis. We have also established roles for brain-derived neurotrophic factor (BDNF) in preventing the apoptosis of neurons produced from stem cells in the hippocampus, a finding that suggests the possibility of increasing the capacity of the brain to replace lost and damaged neurons. In other studies we have found that newly generated neurons are highly sensitive to DNA damage-induced apoptosis because they have low levels of telomerase and the telomere-associated protein TRF2. We have established roles for Notch signaling and a novel protein called Pancortin-2 in neuronal death in stroke. Preclinical studies have shown that intravenous immunoglobulin and gamma-secretase inhibotors are effective in stroke models. More recently, we have shown that neurons express several toll-like receptors, and have provided evidence that activation of two of these receptors (TLR2 and TLR4) can trigger apoptosis in cell culture and animal models of Alzheimer's disease and stroke. In other studies we have revealed important roles for plasma membrane redox enzymes in protecting neurons against apoptosis in experimental models of aging and neurodegenerative disorders.

Agency
National Institute of Health (NIH)
Institute
National Institute on Aging (NIA)
Type
Investigator-Initiated Intramural Research Projects (ZIA)
Project #
1ZIAAG000313-09
Application #
7963919
Study Section
Project Start
Project End
Budget Start
Budget End
Support Year
9
Fiscal Year
2009
Total Cost
$550,272
Indirect Cost
Name
National Institute on Aging
Department
Type
DUNS #
City
State
Country
Zip Code
Zhang, Shi; Eitan, Erez; Wu, Tsung-Yu et al. (2018) Intercellular transfer of pathogenic ?-synuclein by extracellular vesicles is induced by the lipid peroxidation product 4-hydroxynonenal. Neurobiol Aging 61:52-65
Hou, Yujun; Lautrup, Sofie; Cordonnier, Stephanie et al. (2018) NAD+ supplementation normalizes key Alzheimer's features and DNA damage responses in a new AD mouse model with introduced DNA repair deficiency. Proc Natl Acad Sci U S A 115:E1876-E1885
Mattson, Mark P; Moehl, Keelin; Ghena, Nathaniel et al. (2018) Intermittent metabolic switching, neuroplasticity and brain health. Nat Rev Neurosci 19:63-80
Raefsky, Sophia M; Mattson, Mark P (2017) Adaptive responses of neuronal mitochondria to bioenergetic challenges: Roles in neuroplasticity and disease resistance. Free Radic Biol Med 102:203-216
Misiak, Magdalena; Vergara Greeno, Rebeca; Baptiste, Beverly A et al. (2017) DNA polymerase ? decrement triggers death of olfactory bulb cells and impairs olfaction in a mouse model of Alzheimer's disease. Aging Cell 16:162-172
Yao, Pamela J; Manor, Uri; Petralia, Ronald S et al. (2017) Sonic hedgehog pathway activation increases mitochondrial abundance and activity in hippocampal neurons. Mol Biol Cell 28:387-395
Geisler, John G; Marosi, Krisztina; Halpern, Joshua et al. (2017) DNP, mitochondrial uncoupling, and neuroprotection: A little dab'll do ya. Alzheimers Dement 13:582-591
Zhang, Shi; Eitan, Erez; Mattson, Mark P (2017) Early involvement of lysosome dysfunction in the degeneration of cerebral cortical neurons caused by the lipid peroxidation product 4-hydroxynonenal. J Neurochem 140:941-954
Nigam, Saket M; Xu, Shaohua; Kritikou, Joanna S et al. (2017) Exercise and BDNF reduce A? production by enhancing ?-secretase processing of APP. J Neurochem 142:286-296
Cheng, Aiwu; Yang, Ying; Zhou, Ye et al. (2016) Mitochondrial SIRT3 Mediates Adaptive Responses of Neurons to Exercise and Metabolic and Excitatory Challenges. Cell Metab 23:128-42

Showing the most recent 10 out of 82 publications