The protective effect of crocin on the amyloid fibril formation of aβ42 peptide in vitro

Cellular & Molecular Biology Letters

S. Zahra Bathaie¹  Hoda Kheirkhah²  Elmira Bahraminejad²  Arezou Ghahghaei² 

[1] Depatment of Clinical Biochemistry, Faculty of Medical Science, Tarbiat Modares University, Tehran, Iran$$;Department of Biology, Faculty of Science, University of Sistan and Baluchestan, Zahedan, Iran$$

关键词: Alzheimer’s disease;    Neurotic plaques;    Crocin;    Amyloid;    Neurofibrillary;    Aggregation;    Oligomerization;    Protofibrils;    Cytotoxic;   

DOI  :  10.2478/s11658-013-0092-1

学科分类：分子生物学，细胞生物学和基因

来源: Uniwersytet Wroclawski * Wydzial Biotechnologii / University of Wroclaw, Faculty of Biotechnology

【 摘 要 】

Aβ is the main constituent of the amyloid plaque found in the brains of patients with Alzheimer’s disease. There are two common isoforms of Aβ: the more common form, Aβ40, and the less common but more amyloidogenic form, Aβ42. Crocin is a carotenoid from the stigma of the saffron flower and it has many medicinal properties, including antioxidant effects. In this study, we examined the potential of crocin as a drug candidate against Aβ42 amyloid formation. The thioflavin T-binding assay and electron microscopy were used to examine the effects of crocin on the extension and disruption of Aβ42 amyloids. To further investigate the relationship between crocin and Aβ42 structure, we analyzed peptide conformation using the ANS-binding assay and circular dichroism (CD) spectroscopy. An increase in the thioflavin T fluorescence intensity upon incubation revealed amyloid formation in Aβ42. It was found that crocin has the ability to prevent amyloid formation by decreasing the fluorescence intensity. Electron microscopy data also indicated that crocin decreased the amyloid fibril content of Aβ. The ANS-binding assay showed that crocin decreased the hydrophobic area in incubated Aβ42. CD spectroscopy results also showed that the peptide undergoes a structural change to α-helical and β-turn. Our study shows that the anti-amyloidogenic effect of crocin may be exerted not only by the inhibition of Aβ amyloid formation but also by the disruption of amyloid aggregates. Therefore, crocin could be essential in the search for therapies inhibiting aggregation or disrupting aggregation.

【 授权许可】

Unknown