SENS PubMed Publication Search
The effect of α-tocopherol, α- and γ-tocotrienols on amyloid-β aggregation and disaggregation in vitro
Biochem Biophys Rep. 2021 Sep 10;28:101131. doi: 10.1016/j.bbrep.2021.101131.
Nor Faeizah Ibrahim 1, Hamizah Shahirah Hamezah 2, Daijiro Yanagisawa 3, Mayumi Tsuji 4, Yuji Kiuchi 4, Kenjiro Ono 5, Ikuo Tooyama 3
Abstract:
One of the neuropathological hallmarks of Alzheimer's disease (AD)-causing neurodegeneration and consequent memory deterioration, and eventually, cognitive decline-is amyloid-β (Aβ) aggregation forming amyloid plaques. Our previous study showed the potential of a tocotrienol-rich fraction-a mixture of naturally occurring of vitamin E analogs-to inhibit Aβ aggregation and restore cognitive function in an AD mouse model. The current study examined the effect of three vitamin E analogs-α-tocopherol (α-TOC), α-tocotrienol (α-T3), and γ-tocotrienol (γ-T3)-on Aβ aggregation, disaggregation, and oligomerization in vitro. Thioflavin T (ThT) assay showed α-T3 reduced Aβ aggregation at 10 μM concentration. Furthermore, both α-T3 and γ-T3 demonstrated Aβ disaggregation, as shown by the reduction of ThT fluorescence. However, α-TOC showed no significant effect. We confirmed the results for ThT assays with scanning electron microscopy imaging. Further investigation in photo-induced cross-linking of unmodified protein assay indicated a reduction in Aβ oligomerization by γ-T3. The present study thus revealed the individual effect of each tocotrienol analog in reducing Aβ aggregation and oligomerization as well as disaggregating preformed fibrils.
PMID: 34541343
Free Full-Text: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC8435913/