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bioRxiv · 10.1101/2020.04.20.051193

Fruit bromelain derived peptides destabilize growth of amyloidal fibrils

Das, S.·Dutta, S.·Paidi, R. K.·Biswas, S. C.·Halder, U. C.·Bhattacharyya, D.
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Abstract

{beta}-Amyloid deposition as fibrillar plaques in brain is the primary cause of Alzheimers disease. We report potency of cysteine protease fruit bromelain from pineapple in destabilising A{beta} fibrils. Bromelain peptide pool (Mw<500 Da) obtained mimicking human alimentary tract digestion inhibited fibrillation from monomeric and oligomeric states of A and irreversibly dissociated preformed fibrils into small oligomers of varied sizes. Time kinetics was followed by Thioflavin-T assay and microscopic imaging. Synthetic bromelain peptides corresponding to A{beta} sticky region found using ClustalW analysis revealed specificity of peptides in destabilisation of amyloidal structures. Spectra of different molecular states of A{beta} obtained from application of 8-anilino-1-naphthalenesulfonic acid, circular dichroism and Fourier-Transformed Infrared spectroscopy collectively indicated interaction dependent structural change. Probable mechanism for fibril dissociation was thus predicted. Peptides relieved A{beta} cytotoxicity on pheochromcytoma cells and dissociated plaques in AD-type rats prepared by bilateral intracerebroventricular administration of A{beta} in rat brain cortex. Pineapple being a phytoceutical, its efficiency to disaggregate amyloid bodies warrant further investigation. GRAPHICAL ABSTRACT O_FIG_DISPLAY_L [Figure 1] M_FIG_DISPLAY C_FIG_DISPLAY

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Das, S., Dutta, S., Paidi, R. K., Biswas, S. C., Halder, U. C., Bhattacharyya, D.. 2020-04-23. Fruit bromelain derived peptides destabilize growth of amyloidal fibrils. https://doi.org/10.1101/2020.04.20.051193

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