Protective and anti-oxidative effects of curcumin and resveratrol on Aβ-oligomer-induced damage in the SH-SY5Y cell line

https://doi.org/10.1016/j.jns.2022.120356Get rights and content

Highlights

  • •
    Aβ-oligomer efficiently induced SH-SY5Y Alzheimer's disease cell model
  • •
    Curcumin and resveratrol inhibited AβO-induced tau phosphorylation
  • •
    Curcumin and resveratrol decreased ROS generation and oxidative stress
  • •
    Curcumin and resveratrol therapeutic effect on AD

Abstract

Alzheimer's disease (AD) is a degenerative disorder characterized by the loss of synapses and neurons in the brain, and results in the accumulation of amyloid-based neurotic plaques. Amyloid-β oligomers (AβO) are widely accepted as the main neurotoxin that induces oxidative stress and neuronal loss in AD. In this study, an oxidative stress model of the neuroblastoma SH-SY5Y cell line exposed to AβO was established to simulate an AD cell model. Exposure to AβO significantly reduced the viability of cultured SH-SY5Y cells (p < 0.05) and significantly increased intracellular reactive oxygen species (ROS) (p < 0.01). AβO exposure also induced oxidative stress in SH-SY5Y cells. Furthermore, AβO significantly increased the level of hyperphosphorylation of tau at sites T181 and T205 in SH-SY5Y cells (p < 0.01). Using edaravone, a free radical scavenger with neuroprotective properties, as the control, the possible protective and anti-oxidative effects of curcumin (40 μM) and resveratrol (20 μM) were evaluated. The results suggest that curcumin and resveratrol decreased ROS generation, attenuated oxidative stress, inhibited tau hyperphosphorylation, and protected SH-SY5Y cells from AβO damage. Both curcumin and resveratrol are promising supplements or medicine as therapeutic agents for the treatment of AD.

Introduction

Alzheimer's disease (AD), which is a degenerative disorder characterized by the loss of synapses and neurons in the brain, causes the accumulation of amyloid-based neurotic plaques. Various types of medicine have targeted AD in different forms of beta-amyloid (Aβ) to remove plaques or the abnormal accumulation of tissue amyloid [1,2]. To date, however, most have failed in clinical trials. The amyloid cascade hypothesis that dominated the field of AD research for the past few decades has been challenged [3]. In an intense search for the underlying mechanisms of AD, oxidative stress has been recognized as an important factor in the progression of aging and many neurodegenerative diseases, including AD [4]. Oxidative stress causes the loss of mitochondrial function, changes metal homeostasis, increases the production of reactive oxygen species (ROS), and reduces the defense capabilities of antioxidants, thereby directly affecting the synaptic activity of neurons and signal transduction, and eventually leading to cognitive dysfunction [5].
Curcumin (1,7-bis(4-hydroxy-3-methoxyphenyl)-1,6-heptadiene-3,5-dione), is the main active ingredient of the Indian spice turmeric (Curcuma longa L.). It is a lipophilic polyphenol that may function as an anti-cancer, antibiotic, anti-inflammatory, and anti-aging agent, as suggested by several in vitro and in vivo studies, as well as clinical trials [6,7]. Curcumin inhibited the formation and expansion of neurotoxic Aβ fibers, and destroyed their stability [[8], [9], [10]], scavenged the nitric oxide (NO) radical to protect lipids and DNA in the brain from peroxidation [[11], [12], [13]], and also activated glutathione S-transferase through an antioxidant response mechanism [[14], [15], [16]].
Resveratrol (3,5,4′-trihydroxy-trans-stilbene) is a Stilbene (natural phenol) and a phytoalexin produced by several plants in response to injury. It induces a neuroprotective effect when a plant is attacked by pathogens [17]. Resveratrol has been shown to reduce the secretion of intracellular Aβ peptide levels by regulating the proteasome, stimulate α-secretase, induce non-amyloid protein production pathways, and decrease Aβ production [18,19]. Resveratrol interacted directly with Aβ peptides by inhibiting and destroying the formation of Aβ1–42 fibrils [20]. On the other hand, resveratrol blocks oxidative stress, offering protection to neurons and microglia against AD pathogenesis [21,22]. Resveratrol also reduces the Aβ-induced intracellular accumulation of ROS [23,24], and induces the up-regulation of the cellular antioxidant glutathione to prevent oxidative and electrophilic damage [25].
Curcumin and resveratrol have anti-oxidative effects that protect astrocytes [26] and slow down the process of AD through a variety of mechanisms. The antioxidative activity of curcumin and resveratrol may play a role in preventing AD neurodegeneration [27]. Edaravone (3-methyl-1-phenyl-2-pyrazoline-5-one) is a potent free radical scavenger that exerts antioxidant effects by suppressing BACE1 expression and amyloidogenesis through the attenuation of oxidative stress and Aβ-induced GSK3β phosphorylation and suppresses Aβ toxicity by inhibiting Aβ-induced tau protein hyperphosphorylation [28,29]. Edaravone has shown protective effects following ischemic injury and inflammation in the heart, vessel, and brain in experimental studies [30,31]. In the present study, we first established an oxidative stress model of the neuroblastoma SH-SY5Y cell line. Cells were exposed to an Aβ oligomer (AβO) to simulate AD, and edaravone was used as the positive control, to evaluate possible protective and anti-oxidative effects of curcumin and resveratrol on this in vitro model.

Access through your organization

Check access to the full text by signing in through your organization.

Access through your organization

Section snippets

Amyloid β-oligomer preparation

To obtain a concentration of 5 mM, 1 mg of recombinant human Aβ1–42 (#AG968, Sigma-Aldrich, MO, USA) was dissolved in 44 μl of fresh anhydrous dimethyl sulfoxide (DMSO, #D5879, Sigma-Aldrich). This was ultrasonicated for 1 min then added to ice-cold DMEM/F-12 medium (#11039047, Gibco, Grand Island, UK) to achieve a final concentration of 100 μM. This solution was incubated at 4 °C for 24 h then centrifuged at 14,000 ×g for 10 min. The supernatant was transferred to a new tube and stored at

Results

Initially, after artificially preparing AβO, dot blotting analysis was used to verify the preparation of AβO results. The content of AβO increased significantly after preparation (Fig. 1a & 1b, ***p < 0.001). After treatment with different concentrations of AβO (0, 5, 10, 20, 30, and 40 μM), SH-SY5Y cell viability was significantly lower in the AβO-treated groups (5, 10 μM) than in the 0 μM group (Fig. 1c, **p < 0.01). Therefore, 5 μM of AβO was used in subsequent experiments.
In order to

Discussion

The cell viability at higher AβO concentration was not significantly lower than control. it may be because when AβO forms fibrils at a high concentration, its toxicity is reduced [37,38]. A recent study suggested that soluble AβO is the main neurotoxic substance that induces neuronal death and oxidative stress in the early stages of AD [39].
The present study is the first to demonstrate that curcumin and resveratrol improve cell viability in the presence of AβO (Fig. 1), while edaravone was used

Declaration of Competing Interest

The authors have no conflicts of interest.

Acknowledgments

This study was partly supported by a Grant-in-Aid for Scientific Research (B) 17H0419611, (C) 20 K09370, 17H0975609, and 17 K1082709 and by Grants-in-Aid from the Research Committees (Kaji R, Toba K, and Tsuji S) from the Japan Agency for Medical Research and Development 7211700121, 7211800049 and 7211800130.

References (41)

  • J.H. Jang et al.

    Protective effect of resveratrol on beta-amyloid-induced oxidative PC12 cell death

    Free Radic. Biol. Med.

    (2003)
  • Z. Cao et al.

    Potent induction of cellular antioxidants and phase 2 enzymes by resveratrol in cardiomyocytes: protection against oxidative and electrophilic injury

    Eur. J. Pharmacol.

    (2004)
  • A. Daverey et al.

    Pre and post treatment with curcumin and resveratrol protects astrocytes after oxidative stress

    Brain Res.

    (2018)
  • J.D. Rothstein

    Edaravone: a new drug approved for ALS

    Cell

    (2017)
  • L. Zhang et al.

    Edaravone reduces Abeta-induced oxidative damage in SH-SY5Y cells by activating the Nrf2/ARE signaling pathway

    Life Sci.

    (2019)
  • M.A. Martinez et al.

    Use of human neuroblastoma SH-SY5Y cells to evaluate glyphosate-induced effects on oxidative stress, neuronal development and cell death signaling pathways

    Environ. Int.

    (2020)
  • W.L. Klein

    Abeta toxicity in Alzheimer’s disease: globular oligomers (ADDLs) as new vaccine and drug targets

    Neurochem. Int.

    (2002)
  • S. Sarkar et al.

    Estrogen amelioration of Abeta-induced defects in mitochondria is mediated by mitochondrial signaling pathway involving ERbeta, AKAP and Drp1

    Brain Res.

    (2015)
  • L. Mucke et al.

    Neurotoxicity of amyloid beta-protein: synaptic and network dysfunction

    Cold Spring Harb Perspect Med.

    (2012)
  • K. Herrup

    The case for rejecting the amyloid cascade hypothesis

    Nat. Neurosci.

    (2015)

    • Cited by (24)

    View all citing articles on Scopus
    View full text
    © 2022 Elsevier B.V. All rights reserved.