Planta Med 2010; 76(9): 863-868
DOI: 10.1055/s-0029-1240801
Pharmacology
Original Papers
© Georg Thieme Verlag KG Stuttgart · New York

C-Methylflavonoids Isolated from Callistemon lanceolatus Protect PC12 Cells against Aβ-Induced Toxicity

So-Young Park1 , Ji-Youn Lim1 , Wonsik Jeong2 , Seong Su Hong2 , Young Taek Yang3 , Bang Yeon Hwang4 , Dongho Lee2
  • 1Environmental Toxico-Genomic & Proteomic Center, College of Medicine, Korea University, Seoul, Korea
  • 2School of Life Sciences and Biotechnology, Korea University, Seoul, Korea
  • 3Jeju Special Self-Governing Province Agricultural Research and Extension Services, Jeju, Korea
  • 4College of Pharmacy, Chungbuk National University, Cheongju, Korea
Weitere Informationen

Publikationsverlauf

received October 7, 2009 revised Dec. 14, 2009

accepted Dec. 18, 2009

Publikationsdatum:
25. Januar 2010 (online)

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Abstract

Increased beta-amyloid (Aβ) production and its aggregation to the oligomeric state is considered to be a major cause of Alzheimer's disease (AD). Therefore, reducing Aβ-induced neurotoxicity could provide a suitable means of prevention or intervention in the disease course of AD. The neuroprotective effects of isolates from Callistemon lanceolatus DC. (Myrtaceae) against Aβ were evaluated using PC12 cells. To evaluate the effects of Aβ on apoptotic cell death and the effects of Bcl-2 family proteins and caspase-3, TUNEL assays and Western blotting were performed, respectively. Substantial fractionation and purification of the EtOAc-soluble extract of the aerial parts of C. lanceolatus afforded six flavonoids, 4′,5-dihydroxy-6,8-dimethyl-7-methoxyflavanone (1), eucalyptin (2), 8-demethyleucalyptin (3), sideroxylin (4), syzalterin (5), and quercetin (6). Compounds 1, 5, and 6 were found to protect PC12 cells effectively against Aβ-induced toxicity. In particular, compound 1 showed the most promising neuroprotective effect with an ED50 value of 6.7 µM in terms of decreasing Aβ-induced apoptotic cell death, and this was accompanied by a decrease in caspase-3 activation and an increase in Bcl-2/Bax ratio. These results suggest that compound 1 could be developed as a candidate anti-AD agent due to its attenuation of Aβ-induced apoptotic cell death.

References

Ph.D. Dongho Lee

School of Life Sciences and Biotechnology
Korea University

Anam-Dong

Seongbuk-Gu

136–713 Seoul

Korea

Telefon: + 82 2 32 90 30 17

Fax: + 82 29 53 07 37

eMail: dongholee@korea.ac.kr