Novel AmyP53 Peptide Shows Dual Promise for Alzheimer’s and Parkinson’s Diseases

Recent studies suggest a different approach to elaborating therapies for these neurodegenerative disorders. In general, one of the typical pathological hallmarks of Parkinson’s (PD) and Alzheimer’s disease (AD) is the misfolding and accumulation of specific proteins like the α-synuclein and the β-amyloid, which, in high levels, are detrimental to the brain cells.^[4] Even though most of the research effort is used to prevent the accumulation of these proteins, there is still no cure for neurodegeneration. However, several studies have pointed out that amyloids (β-amyloid) and α-synuclein oligomers are more linked to the symptoms of both disorders.^[1-3] Oligomers are toxic and aggregate early before forming α-synuclein clumps and β-amyloid plaques—equally.^[3] These oligomers are formed from the self-assembly of a few molecules of amyloid proteins. There are two oligomers: (1) the soluble oligomers and (2) the membrane-associated oligomers.^[1]

Interestingly, only the membrane-associated oligomers are noxious when interacting with the plasma membrane.^[3] Some articles refer to AD as a membrane disorder.^[3] The membrane-oligomer interaction is generally arbitrated by molecules called gangliosides.^[2] Gangliosides are assembled micro-domains of the membrane that form lipid rafts. ^[2,5] Gangliosides are used as connection sites by α-synuclein and β-amyloid proteins.^[3] For a membrane-oligomer connection, first, they need to bind to gangliosides.^[2] Once the oligomers bind the gangliosides, they form “amyloid pores”.^[2,3] Amyloid pores are slight channels in which unregulated Ca⁺² ions enter the cell, generating a calcium imbalance in brain cells.^[3] In normal conditions, calcium is crucial in plasticity, signaling between neurons, synaptic transmission, and transport.^[3,6]

On the other hand, the unregulated entrance of Ca⁺² ions inside the cells caused an increase in toxicity and led to apoptosis (cell death).^[4] In addition, high levels of Ca⁺² ions stimulate the activation of pathways for the overproduction of other proteins like the tau protein, another pathological hallmark of AD. ^[6] Oxidative stress, synaptic decline, and plasticity have also been observed.^[3] Therefore, finding molecules able to bind and block the gangliosides can help prevent amyloid-related oligomers from attaching and forming the amyloid pores, thus helping reverse or prevent the development of AD and PD.^[1,3,5]

AmyP53 is a peptide (KEGVLYVGHHTK) used in recent investigations to develop new treatments for AD and PD.^[3] AmyP53 was created with the necessary binding properties of the oligomers to bind the gangliosides, thus avoiding the amyloid oligomers to bind and form the amyloid pores (see Fig. 1).^[3] Once the AmyP53 prevents the amyloid pore formation, the Ca⁺² ions maintain its average level. AmyP53 also prevents neuroinflammation, synaptic loss, neuronal death, tau misfolding, and mitochondrial dysfunction, which can all cause the development of neurodegenerative disorders, especially AD and PD.^[1-4] To develop this peptide, the investigators identified recognition sites in the ganglioside structures and then tested different molecules that share the molecular characteristics for binding. ^[1-3] The Amyp53 peptide can be administered successfully through intravenous and intranasal administration.^[3] However, the recommended method is the intranasal administration (nasal spray) (see Fig.2). ^[1,3] This peptide can be used as a treatment for both AD and PD because of the mechanism used. Recent studies have also shown that AmyP53 has excellent stability in temperatures up to 45 ◦C for months without signs of degradation.^[3] In addition, the AmyP53 can cross the blood-brain barrier through both the intranasal and intravenous administration, where higher amounts of the peptide are found in the brain than in the blood.^[1]

Shows the mechanism in which AmyP53 imitates the neurotoxicity pathway of Parkinson’s and Alzheimer’s disease. By using the exact mechanism, AmyP53 blocks the formation of amyloid pores in brain cell membranes.^[3]

Figure 1.

AmyP53 presents a remarkable capacity to decrease amyloid pore formation (see Fig.2).^[3] Some articles testing in vivo the safety of administering this peptide demonstrated that AmyP53 is safe and does not cause side effects in the brain’s physiology, histology, and behavior.^[1,2] The different studies demonstrated the efficacy of AmyP53 in the prevention of the development of both AD and PD since the formation of amyloid pores may be the beginning of the disease.^[2] AmyP53 is a great alternative to noninvasive therapy for AD and PD. Identifying two routes (through the olfactory bulbs or the systemic circulation) demonstrated that this peptide could easily pass the blood-brain barrier. AmyP53 is the first peptide targeting gangliosides. The several articles in which Amyp53 has been tested in different mouse models showing promising results give this peptide an advantage over others currently under investigation. ^[2-5]

Routes of AmyP53 reaching the brain by direct and secondary pathways.^[3]

Figure 2.

AmyP53 has the full potential to prevent the development of neurodegenerative disorders through the following:

• Prevention of neuroinflammation
• Decrease of synaptic loss
• Prevention of mitochondrial dysfunction
• Prevention of apoptosis
• Avoids the formation of amyloid pores
• Ca+2 homeostasis
• Decreased oligomers toxicity
• Increases neuroplasticity

The unique peptide AmyP53 presents an opportunity to develop a new peptide therapy against two of the most detrimental neurodegenerative disorders (AD and PD). AmyP53 has been tested in vivo and in vitro, showing excellent stability, effectiveness, and delivery trespassing the blood-brain barrier without side effects.

References

1. Azzaz, F., Chahinian, H., Yahi, N., Fantini, J., & Di Scala, C. (2023). AmyP53 Prevents the Formation of Neurotoxic β-Amyloid Oligomers through an Unprecedent Mechanism of Interaction with Gangliosides: Insights for Alzheimer’s Disease Therapy.International journal of molecular sciences, 24(2), 1760.
2. Azzaz, F., Yahi, N., Di Scala, C., Chahinian, H., & Fantini, J. (2022). Ganglioside binding domains in proteins: Physiological and pathological mechanisms.Advances in protein chemistry and structural biology, 128, 289-324.
3. Di Scala, C., Armstrong, N., Chahinian, H., Chabrière, E., Fantini, J., & Yahi, N. (2022). AmyP53, a Therapeutic Peptide Candidate for the Treatment of Alzheimer’s and Parkinson’s Disease: Safety, Stability, Pharmacokinetics Parameters and Nose-to Brain Delivery. International journal of molecular sciences, 23(21), 13383.
4. El-Battari, A., Rodriguez, L., Chahinian, H., Delézay, O., Fantini, J., Yahi, N., & Di Scala, C. (2021). Gene therapy strategy for Alzheimer’s and Parkinson’s diseases aimed at preventing the formation of neurotoxic oligomers in SH-SY5Y cells.International Journal of Molecular Sciences, 22(21), 11550.
5. Fantini, J. (2023). Lipid rafts and human diseases: why we need to target gangliosides. FEBS Open Bio.
6. Fantini, J., Chahinian, H., & Yahi, N. (2020). Progress toward Alzheimer’s disease treatment: Leveraging the Achilles’ heel of Aβ oligomers?. Protein Science, 29(8), 1748-1759.
7. Pradhan, K., Das, G., Mondal, P., Khan, J., Barman, S., & Ghosh, S. (2018). Genesis of neuroprotective peptoid from Aβ30–34 inhibits Aβ aggregation and AChE activity. ACS Chemical Neuroscience, 9(12), 2929-2940.

Appendix

Table 1. Chemical properties of the AmyP53 peptide^[3]

Figure 3. This image shows the efficiency of AmyP53 in decreasing amyloid pore formation.^[3]