Skip to main page content
U.S. flag

An official website of the United States government

Dot gov

The .gov means it’s official.
Federal government websites often end in .gov or .mil. Before sharing sensitive information, make sure you’re on a federal government site.

Https

The site is secure.
The https:// ensures that you are connecting to the official website and that any information you provide is encrypted and transmitted securely.

Access keys NCBI Homepage MyNCBI Homepage Main Content Main Navigation
. 2020 Aug;35(6):923-931.
doi: 10.1007/s11011-019-00520-2. Epub 2020 May 4.

Effect of AmyTrap, an amyloid-β binding drug, on Aβ induced mitochondrial dysfunction and tau phosphorylation in cultured neuroblastoma cells

Omkar Gandbhir  1 , Pazhani Sundaram  2
Affiliations

Effect of AmyTrap, an amyloid-β binding drug, on Aβ induced mitochondrial dysfunction and tau phosphorylation in cultured neuroblastoma cells

Omkar Gandbhir et al. Metab Brain Dis. 2020 Aug.

Abstract

Alzheimer's Disease (AD) is the most common cause of dementia, affecting 25 million people worldwide. Accumulation of Amyloid-β (Aβ) in the mitochondria has been shown to adversely affect key enzymes including pyruvate dehydrogenase (PDH), succinate dehydrogenase (SDH), oxoglutarate dehydrogenase (OGDH). Accumulation of Aβ is also believed to increase Tau expression and pathology. Tau, in its toxic state, results in synaptic damage causing memory and cognitive dysfunction. We are developing a drug to treat AD namely AmyTrap. The active pharmacological ingredient is a retro inverso, Aβ-binding peptide which sequesters Aβ. We wanted to examine the effect of AmyTrap peptide on Aβ-induced mitochondrial dysfunction and Tau phosphorylation. Therefore, we treated SH-SY5Y neuroblastoma cells with wild-type Aβ, a mutant AβY10A, AmyTrap peptide (RI-peptide), or Aβ and RI-peptide for 72 h. The mutant AβY10A is known to impact the self-aggregating property of Aβ as this Tyr10 is essential for self-aggregation. As expected, AβY10A reversed PDH, OGDH and SDH dysfunction to near normal levels. Further, AβY10A successfully reversed Tau phosphorylation, suggesting that Tyr10 is also associated with Aβ-induced cytotoxicity. RI-peptide was able to significantly reverse SDH dysfunction with limited effect on PDH and Tau phosphorylation. The findings are suggestive that the Tyr10 on Aβ plays a critical role in the self-aggregation. Further studies are warranted to expand these findings.

Keywords: Alzheimer’s disease; AmyTrap; Amyloid; Mitochondria; Retro-inverso peptide; SH-SY5Y neuroblastoma cells.

PubMed Disclaimer

Conflict of interest statement

Declaration of Interest: None

Figures

Fig 1
Fig 1. The Amytrap peptide.
An Aβ binding retro-inverso tetrameric peptide consisting of 4 chains of the same synthetic peptide that are linked to Lysine and Cysteine
Fig 2
Fig 2. Analysis of Expression of Mitochondrial Enzymes.
Each enzyme is represented by a representative immunoblot and graph of the band intensity (A) Pyruvate Dehydrogenase (43 kDa), (B) ATP Citrate Lyase (121 kDa), (C) Succinate Dehydrogenase (72 kDa), (D) Oxoglutarate Dehydrogenase (116 kDa). Treatment groups are Untreated, wild-type Aβ42 (4 μM), mutant AβY10A (4 μM) or a combination of Aβ42 (4 μM) and RI-peptide (10 μM). Band intensities are from 3 different experiments and values are represented as Mean ± SD. Significance was calculated by Student’s t-test against the untreated neuroblastoma group for all treatments and then between Aβ and AβY10A or Aβ and Aβ + RI-peptide. A * indicates p < 0.05, ** indicates p < 0.01 and *** indicates p < 0.001.
Fig 3
Fig 3. Expression of phosphorylated Tau.
Analysis of phosphorylated Tau was performed through ImageJ analysis. The images of the immunoblot of Tau is shown below the graph. Treatment groups are Untreated, wild-type Aβ42 (4 μM), mutant AβY10A (4 μM) or a combination of Aβ42 (4 μM) and RI-peptide (10 μM). Significance was calculated against Untreated Neuroblastoma group by Student’s t-test. Experiments were performed in triplicate. Values are represented as Mean ± SD. A * indicates p < 0.05, ** indicates p < 0.01.
Fig 4
Fig 4. Intracellular Accumulation of Amytrap (RI-Peptide).
Analysis of the presence of intracellular RI-peptide was performed through ImageJ. Treatment groups are Untreated, RI-peptide (10 μM), or a combination of Aβ42 (4 μM) and RI-peptide (10 μM). A positive control consisting of a known concentration of RI-peptide (100 ng) was utilized to evaluate the intracellular concentration of peptide observed between treatment groups. The image of the immunoblot of RI-peptide is shown below the graph. Significance was calculated against Untreated Neuroblastoma group by Student’s t-test. Experiments were performed in triplicate. Values are represented as Mean ± SD. A ** indicates p < 0.01.
See this image and copyright information in PMC

Similar articles

See all similar articles

Cited by

References

    1. A Massaad C Neuronal and vascular oxidative stress in Alzheimer’s disease. Current Neuropharmacol. 2011. December 1;9(4):662–73. - PMC - PubMed
    1. Agholme L, Lindström T, Kågedal K, Marcusson J, Hallbeck M. An in vitro model for neuroscience: differentiation of SH-SY5Y cells into cells with morphological and biochemical characteristics of mature neurons. J Alzheimers Dis. 2010. January 1;20(4):1069–1082. - PubMed
    1. Alzheimer’s Association, 2006. Early onset dementia: a national challenge, a future crisis Alzheimer’s Association, Washington, DC.
    1. Alzheimer’s Association, 2012. Alzheimer’s Disease Facts and Figures, Available at: http://www.alz.org/downloads/Facts_Figures. - PubMed
    1. Bubber P, Haroutunian V, Fisch G, Blass JP, Gibson GE. Mitochondrial abnormalities in Alzheimer brain: mechanistic implications. Ann Neurol. 2005. May;57(5):695–703. - PubMed

Publication types

MeSH terms