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Hallmarks of this disease include the development of the senile
plaques of the amyloid beta peptide, and neurofibrillary tangles. These
are present in the hippocampus, prefrontal cortex, cerebellum, and
temporal lobe; regions of the brain that are involved with learning,
memory, and behavior. The senile plaques are formed by the cleavage
of the amyloid precursor protein (APP). Formation of these plaques
cause connections between nerve cells to be destroyed, leading to
decreased cell density, and ultimately neuronal cell death. The
neurofibrillary tangles are affected by the tau protein, located on the
microtubules of the neuron, which is hyperphosphorylated and then stick
to each other.12

There are two specific objectives that will be utilized to determine if
mitoNEET is a potential cure target for AD. First, cell culture
techniques will be used to examine proteins in an Alzheimer’s
disease model. The cell line being studied is a mouse neuroblastoma
(N2A) cell line due to the cells being hearty, allowing reliable growth.
Second, fluorescence microscopy will be used to study changes in
the trafficking and expression of mitoNEET using Aβ1→42 and current
therapeutics. MitoNEET can be labeled with GFP. The changes in
the measured fluorescent signal correspond to the concentration of
the protein within the cells.

MitoNEET is a newly
discovered mitochondrial
protein. The mitoNEET is
an integral protein localized in the
outer mitochondrial membrane
(OMM), its name is based on
its subcellular localization and
the presence of the amino acid
sequence Asn-Glu-Glu-Thr (NEET).
The first 32 residues present within
the mitoNEET are an essential
section of amino acids within the
Figure 3. Structure and possible functional
implications of mitoNEET. Paddock, Mark L.;
predicted transmembrane
Wiley, Sandra E.; Axelrod, Herbert L.; Cohen, Aina E.; Roy,
domain. This domain directs the
Melinda; Abresch, Edward C.; Capraro, Dominique;
Anne N.; Nechushtai, Rachel; Dixon, Jack E.;
mitoNEET to the outer membrane and Murphy,
Jennings, Patricia A. MitoNEET is a uniquely folded 2Fe​2S outer mitochondrial membrane protein stabilized by piog
is responsible for its colocalization.
litazone. PNAS. 2007. 104(36). 14342-14347.
MitoNEET is also identified as
part of the unique 39 amino acid sequence, CDGSH, a domain in
residues 55-93 that act similarly to a zinc finger and is likely involved with
iron binding. The protein also contains a N-terminal α-helix with a redox
active iron-sulfur domain, [2Fe-2S]. These components have shown that
mitoNEET is able to play roles in the regulation of energy metabolism in
the mitochondria.14

MitoNEET In The Presence
of Isoproterenol

Figure 1. Process of hyperphosphorylation Figure 2. Cleavage of APP to form Aβ
senile plaques.
of tau protein.
Verwilst, Peter; Kim, Hyeong Seok; Kim, Soobin; Kang, Chulhun;
Kim, Jong Seung. Sheffing light on the tau protein aggregation: the
progress in developing high selective fluorophores. Chemical
Society Reviews. 2018. 47(7). 2249-2265

Preliminary studies were completed to verify that mitoNEET was
upregulated when exposed to isoproterenol. In the study, N2a cells were
exposed to 1 µM, 10 µM and 100 µM of isoproterenol and then compared
to the control. The upregulation was found utilizing fluorescence
microscopy tagged with Green Fluorescence Protein (GFP). A t-test was
also completed to show that analysis completed was significant.

Cheignon, C.; Tomas, M.; Bonnefont-Rousselot, D.; Faller, P.;
Hureau, C.; Collin, F. Oxidative stress and the amyloid beta
peptide in Alzheimer’s disease. Redox Biology. 2018. 14. 450464.

A new study was performed to determine if mitoNEET expression
was changed when exposed to donepezil, a current treatment or
AD. In the study, N2a cells were exposed to 5 µM, 50 µM, and
500 µM donepezil and then compared to the control. MitoNEET
concentration showed no change when utilizing fluorescence
microscopy tagged with Green Fluorescence Protein (GFP).

Figure 7. mitoNEET-GFP + 0 µM donepezil

Figure 8. mitoNEET-GFP + 5 µM donepezil

Figure 9. mitoNEET-GFP + 50 µM donepezil

Figure 10. mitoNEET-GFP + 500 µM donepezil

Utilizing the processing program Image J, the average
concentration of donepezil was found for the control, 5 µM, 50 µM,
and 500 µM. The mean fluorescence intensities (a.u.) were
determined to be 163, 144, 160, and 189, respectively. Also, the
average raw integrated densities were determined to be 399000,
295000, 310000, and 311000, respectively.
mitoNEET-GFP ± donepezil

3.
4.
5.
6.

7.
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9.
10.
11.
12.
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14.

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17.

Figure 5. mitoNEET-GFP

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50
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1 uM

10 uM

50 µM

500 µM

Control

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50 µM

500 µM

2017 Alzheimer's Disease Facts and Figures. www.alz.org/facts/.
Mane, Deepali J.; Kanase, Vanita; Ansari, Imtiyaz. An overview of treatment for Alzheimer’s disease. European Journal of Biomedical and
Pharmaceutical Sciences. 2018, 5 (6), 1-6.
Jones, Simon Vann Kounatidis. Nuclear factor kappa B and Alzheimer disease, unifying genetic and environmental risk factors from cell to
humans. Frontiers in Immunology. 2017, 8, 1805/1-1805/9.
Lovell, M. A.; Markesbery, W. R., Oxidative DNA damage in mild cognitive impairment and late-stage Alzheimer's disease. Nucelic Acids Res.
2007, 35 (7497-7504)
Moreira, P. I.; Carvalho, C.; Zhu, X.; Smith, M. A.; Perry, G., Mitochondrial dysfunction is a trigger of Alzheimer's disease pathophysiology.
Biochimica et Biophysica Acta. 2010, 1802, 2-10.
Habener, Anika; Chowdhury, Arpita; Echtermeyer, Frank; Lichtinghagen, Ralf; Theilmeier, Gregor; Herzog, Christine. MitoNEET protects HL-1
cardiomyocytes from oxidative stress mediated apoptosis in an in vitro model of hypoxia and reoxygenation. PLoS One. 2016, 11 (5),
e0156054/1-e0156054/18.
Kril, J. J.; al., e., Neuron loss from the hippocampus of Alzheimer's disease exceeds extracellular neurofibrillary tangle formation. Acta
Neuropathol. 2002, 103, 370-376.
Fox, N. C.; al., e., Serial magnetic resonance imaging of cerebral atrophy in preclinical Alzheimer's disease. Lancet 1999, 353, 2125.
LaFerla, F. M., Calcium dyshomeostasis and intracellular signalling in Alzheimer's disease. Nat. Rev. Neurosci. 2002, 3, 862-872.
Bossers, K.; al., e., Concerted changes in transcripts in the prefrontal cortex precede neuropathology in Alzheimer's disease. Brain: A Journal of
Neurology 2010, 133, 3699-3723.
N.C. Berchtold, e. a., Synaptic genes are extensively downregulated across multiple brain regions in normal human aging and Alzheimer's
disease. Neurobiol. Aging 2013, 35, 1653-1661
Mudher, A.; Lovestone, S., Alzheimer's disease - do tauists and baptists finally shake hands? Trends Neurosci. 2002, 25 (1), 22-26.
Terry, A. V.; Buccafusco, J. J., The cholinergic hypothesis of age and Alzheimer's disease-related cognitive deficits: recent challenges and their
implications for novel drug development. Journal of Pharmacolgy and Experimental Therapeutics 2003, 306 (3), 821-827.
Paddock, Mark L.; Wiley, Sandra E.; Axelrod, Herbert L.; Cohen, Aina E.; Roy, Melinda; Abresch, Edward C.; Capraro, Dominique; Murphy, Anne
N.;
Nechushtai,
Rachel;
Dixon,
Jack
E.;
Jennings,
Patricia
A.
MitoNEET
is
a
uniquely
folded
2Fe2S outer mitochondrial membrane protein stabilized by pioglitazone. PNAS. 2007. 104(36). 14342-14347.
Treinin, M.; Papke, RL; Nizri, E.; David-Ben.; Mizrachi, T.; Brenner, T. Role of the α7 Nicotinic Acetylcholine Receptor and RIC-# in the
Cholinergic Anti-inflammatory Pathway. NCBI. 2017. 17(2). 90-99
Sun, Julianna l.; Stokoe, Sarah A.; Roberts, Jessica P.; Sathler, Matheus F.; Nip, Kaila A.; Shou, Jiayi; Ko, Kaitlyn; Tsunoda, Susan; Kim, Seonil.
Co-activation of selective of nicotinic acetylcholine receptors is required to reverse beta amyloid-induced Ca2+ hyperexcitation. Neurobiology of
Aging. 2019.
Lykhmus, Olena; Kalashnyk, Olena; Koval, Lyudmyla; Voytenko, Larysa; Uspenska, Kateryna; Komisarenko, Serhiy; Deryabina, Olena;
Shuvalova, Nadia; Kordium, Vitalii; Ustymenko, Alina; Kyryk, Vitalii; Skok, Maryna. Mesenchymal Stem Cells or Interleukin-6 Improve Episodic
Memory of Mice Lacking α7 Nicotinic Acetylcholine Receptors. Neuroscience (Amsterdam, Netherlands). 2019. 413. 31-44.

mitoNEET-GFP ± isoproterenol
Raw Integrated Density

**

Control

5 µM

450000
400000
350000
300000
250000
200000
150000
100000
50000
0

Figure 6. mitoNEET-GFP + 100 µM isoproterenol

mitoNEET-GFP ± isoproterenol
Mean Flourescence
Intensity (a.u)

Research related to AD has been ongoing for several years. Past
hypotheses have focused on the decreased activity of the acetylcholine
esterase and the decreased expression of nicotinic and muscarinic
receptors. Along with the accumulation of the amyloid beta formed by
the cleavage of the APP, and the hyperphosphorylation of the tau
protein. These hypotheses have only allowed for alleviation of the
symptoms of AD rather than a cure.13-14 By focusing on this more
recently developed hypothesis, mitochondrial dysfunction is a new
avenue provided to potentially find a cure.

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60
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Control

1.
2.

mitoNEET-GFP ± donepezil
Raw Integrated Density

AD is one of the most common neurodegenerative diseases and is the
sixth leading cause of death in the United States. This disease is
characterized by memory loss, language difficulties, and personality
changes. This leads to neuron death, increased levels of reactive
oxygen species, altered calcium signaling, and alternations in gene
expression and transcription mechanisms.4,8-11 There is currently no
cure for AD.

The overarching goal of this research project is to understand the
mitochondrial dysfunction occurring in Alzheimer’s disease (AD) by
evaluating changes in the mitochondrial protein, mitoNEET. This idea
comes from the belief that mitochondrial dysfunction causes the
formation of plaques and tangles in the brain of AD patients. Previous
studies was completed on mitoNEET to identify it as a potential drug
target for Type II diabetes (T2D) treatment. MitoNEET showed great
potential as a target binding site in T2D trial. It is hoped that similar
results will occur in our studies since T2D, and AD are
conformationally similar.

Mean Fluorescence Intensity
(a.u)

Alzheimer’s disease (AD) is a neurodegenerative disease that affects
over 5 million Americans. The disease is characterized by the
formation of senile plaques of the amyloid beta and neurofibrillary
tangles within the brain that can impair the patient’s memory and
behavior. These symptoms of AD develop slowly and worsen over
time. Currently there is no known cause or cure for AD, therefore
treatment is restricted to alleviating symptoms. A new approach to AD
focuses on mitochondrial dysfunction, which is when the mitochondria
release reactive oxidative species that cause damage and changes to
the expression of tissues, proteins, and genes. MitoNEET is a newly
discovered mitochondrial protein that is thought to regulate
bioenergetics in cells. The focus of our research is to help resolve the
mechanism of AD by identifying potential targets for treatment.
Fluorescence microscopy is used to evaluate changes in protein
expression. This was used to assess changes in protein expression
when exposed to current AD therapeutics. One treatment is
isoproterenol, which is a bronchodilator that has been shown to
upregulate mitoNEET. Our preliminary studies use fluorescence
microscopy to verify that isoproterenol upregulated the expression of
mitoNEET in N2a cells after a 24-hour exposure. The results showed a
two-fold increase in the relative integrated density when exposed to 1,
10, 100 uM of isoproterenol. Further studies will investigate mitoNEET
regulation in response AD therapeutics.

100 uM

1200000

**

1000000

This work was supported, in whole or in part, by Slippery Rock
University, and the SRU Chemistry Department. We would also
like to thank Dr. Christopher Richards (University of Kentucky) for
providing cell lines and constructs.

800000
600000
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0

Control

1 uM

10 uM 100 uM