Coumarin derivatives - the structure-function analysis of the anti-amyloid potential

Coumarin derivatives - the structure-function analysis of the anti-amyloid potential

Sekcia: 
Rok:
2022

Celkové hodnotenie

Vedecká práca
75%
Prevedenie (dizajn)
75%
Diskusná interakcia
75%
PoužívateľVedecká prácaDizajnDiskusná interakcia
RNDr. Zuzana Bednáriková PhD. 100%100%100%
RNDr. Erika Kellerová PhD.100%100%100%

Coumarin derivatives - the structure-function analysis of the anti-amyloid potential

Barbora Borovska1 , Paweł Krupa2 , Zuzana Bednarikova , Slavka Hamulakova3 , Mai Suan Li4 , Zuzana Gazova ,
1 Institute of Experimental Physics, Slovak Academy of Sciences, Košice, Slovakia
2 Institute of Physics, Polish Academy of Sciences, Al. Lotnikow 32/46, 02-668 Warsaw, Poland
3 Institute of Chemistry, Pavol Jozef Šafarik University in Košice, Slovakia
4 Life Science Lab, Institute for Computational Science and Technology, Quang Trung Software City, Tan Chanh Hiep Ward, District 12, Ho Chi Minh City 729110, Vietnam
borovska@saske.sk

Amyloid aggregates are highly stable, insoluble fibrillar protein structures formed and accumulated in vital organs, associated with many currently incurable diseases (Alzheimer's disease or various systemic amyloidoses). Identifying the molecules with the capacity to inhibit amyloid fibrils formation and/or destroy amyloid fibrils is of high necessity due to their possible use as drugs. However, a significant polymorphism between the amyloid fibrils of different proteins complicates the hunt for new treatment agents.

We studied the anti-amyloid activity of mono-coumarin and bis-coumarin derivatives on two structurally distinct proteins forming amyloid aggregates – hen egg-white lysozyme (HEW lysozyme, a globular protein) and Aβ42 peptide (an intrinsically disordered peptide). The selected mono-coumarin derivatives differed by the functional group modifying the coumarin molecule. The bis-coumarin derivatives consisted of two coumarin moieties connected by the piperazine linker of different lengths. Our goal is to determine the relationship between the structure of mono/bis-coumarin derivatives (number of coumarin moieties, modifying functional group, the linker length) and their anti-amyloid potential.

Using the ThT fluorescence assay, we determined that the presence of two coumarin moieties is essential for compounds' anti-amyloid activity as mono-coumarin derivatives did not lead to significant inhibition or the destruction of amyloid fibrils of both studied proteins. In the case of bis-coumarin derivatives, the inhibitory effect was observed only at the highest derivative concentration for both studied proteins. The most effective was the BC7 compound with the longest linker. Interestingly, even though none of the studied bis-coumarin derivatives have the ability to destroy the HEW lysozyme amyloid fibrils, they significantly reduced the ThT fluorescence intensity of Aβ42 amyloid fibrils, pointing to strong destruction activity. The extent of the bis-coumarins' destroying effects on Aβ42 amyloid fibrils depended on the linker length, with the highest efficiency again attributed to the compound BC7 (with the longest linker). The results of the ThT fluorescence assay were further confirmed using atomic force microscopy, and a better understanding of the mechanism behind the anti-amyloid activity was provided by in silico analysis.

Poďakovanie: 

This work was supported by the Slovak Research and Development Agency under Contract no. APVV-18-0284 and SK-TW-21-0004; Slovak Grant Agency VEGA 02/0176/21, ITMS 313011T533 (DIAGNAD), the Operational Programme Integrated Infrastructure funded by the ERDF, the project implementation BIOVID-19 (ITMS2014 + 313011AVG3) and NANOVIR (ITMS2014 + 313011AUW7) and Grant program for SAS Ph.D. Students APP0293.

Diskusia

Nice work, apparently linked to the presented study by Olga Parmar et al. devoted to this important field of research. It is known that deposition of Aβ in the brain is a pathological hallmark of Alzheimer's disease and that there are two major isoforms of Aβ: the 42-residue Aβ42 and the 40-residue Aβ40. It is suggested that specific interactions between Aβ42 and Aβ40 and a ratio Aβ42 to Aβ40 play an important role in the pathogenesis of the disease. Did you use this peptide in your research?

iwa

Thank you very much for your question. Yes, we are aware of the two isoforms of Aβ peptide connected to the pathology of Alzheimer´s disease. In the presented research we used only the 42 residues long-form of Aβ peptide (as the representative of IDPs), as the Aβ42 is thought to be the more reactive and thus more toxic form of Aβ peptide, participating in the formation of toxic oligomeric species and amyloid fibrils. Since the aim of this study was to focus on the structure-function analysis of potential amyloid inhibitors, rather than using the Aβ40 as well, we prioritized the differences in the activity of the compounds on Aβ42 (IDP) and HEW lysozyme (globular protein). However, in some of our studies, we use the Aβ40 as well. It all depends on the character and the main aim of the particular study. 

 

Thank you very much for the explanation and immediate reply.

Best wishes for your research.

iwa