Curcumin inhibits aggregation of α-synuclein
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Aggregation of amyloid-beta protein (Aβ) is a key pathogenic event in Alzheimer’s disease (AD). Curcumin, a constituent of the Indian spice Turmeric is structurally similar to Congo Red and has been demonstrated to bind Aβ amyloid and prevent further oligomerization of Aβ monomers onto growing amyloid β-sheets. Reasoning that oligomerization kinetics and mechanism of amyloid formation are similar in Parkinson’s disease (PD) and AD, we investigated the effect of curcumin on α-synuclein (AS) protein aggregation. In vitro model of AS aggregation was developed by treatment of purified AS protein (wild-type) with 1 mM Fe3+ (Fenton reaction). It was observed that the addition of curcumin inhibited aggregation in a dose-dependent manner and increased AS solubility. The aggregation-inhibiting effect of curcumin was next investigated in cell culture utilizing catecholaminergic SH-SY5Y cell line. A model system was developed in which the red fluorescent protein (DsRed2) was fused with A53T mutant of AS and its aggregation examined under different concentrations of curcumin. To estimate aggregation in an unbiased manner, a protocol was developed in which the images were captured automatically through a high-throughput cell-based screening microscope. The obtained images were processed automatically for aggregates within a defined dimension of 1–6 μm. Greater than 32% decrease in mutant α-synuclein aggregation was observed within 48 h subsequent to curcumin addition. Our data suggest that curcumin inhibits AS oligomerization into higher molecular weight aggregates and therefore should be further explored as a potential therapeutic compound for PD and related disorders.
KeywordsAlpha-synuclein Curcumin Parkinson’s disease Lewy bodies Amyloid Polyphenol
Dementia with Lewy bodies
We would like to thank Dr. Michele Goedert for the AS construct. We are grateful to Dr. John Trojanowski for antibodies. We would like to thank Dr. Alfred Heller for gifting the MN9D cell line. This work was supported by grants from the American Federation on Aging Research and the National Institute on Aging (K08 AG20764). Dr. Galvin is a recipient of the Paul Beeson Physician Faculty Scholar Award in Aging Research. This project was also supported by generous gifts from the Alan A. and Edith L. Wolff Charitable Trust and the Blue Gator Foundation. Dr. Pandey was partly supported by Missouri Alzheimer Disease and Related Disorder Program for this work.
- 3.Aggarwal S, Ichikawa H, Takada Y, Sandur SK, Shishodia S, Aggarwal BB (2006) Curcumin (diferuloylmethane) down-regulates expression of cell proliferation and antiapoptotic and metastatic gene products through suppression of IkappaBalpha kinase and Akt activation. Mol Pharmacol 69:195–206PubMedGoogle Scholar
- 10.Cheng AL, Hsu CH, Lin JK, Hsu MM, Ho YF, Shen TS, Ko JY, Lin JT, Lin BR, Ming-Shiang W, Yu HS, Jee SH, Chen GS, Chen TM, Chen CA, Lai MK, Pu YS, Pan MH, Wang YJ, Tsai CC, Hsieh CY (2001) Phase I clinical trial of curcumin, a chemopreventive agent, in patients with high-risk or pre-malignant lesions. Anticancer Res 21:2895–2900PubMedGoogle Scholar
- 17.Engelender S, Kaminsky Z, Guo X, Sharp AH, Amaravi RK, Kleiderlein JJ, Margolis RL, Troncoso JC, Lanahan AA, Worley PF, Dawson VL, Dawson TM, Ross CA (1999) Synphilin-1 associates with alpha-synuclein and promotes the formation of cytosolic inclusions. Nat Genet 22:110–114PubMedCrossRefGoogle Scholar
- 35.Prasad JE, Kumar B, Andreatta C, Nahreini P, Hanson AJ, Yan XD, Prasad KN (2004) Overexpression of alpha-synuclein decreased viability and enhanced sensitivity to prostaglandin E(2), hydrogen peroxide, and a nitric oxide donor in differentiated neuroblastoma cells. J Neurosci Res 76:415–422PubMedCrossRefGoogle Scholar
- 37.Seeram NP, Adams LS, Henning SM, Niu Y, Zhang Y, Nair MG, Heber D (2005) In vitro antiproliferative, apoptotic and antioxidant activities of punicalagin, ellagic acid and a total pomegranate tannin extract are enhanced in combination with other polyphenols as found in pomegranate juice. J Nutr Biochem 16:360–367PubMedCrossRefGoogle Scholar