Quercetin inhibits okadaic acid-induced tau protein hyperphosphorylation through the Ca2+‑calpain‑p25‑CDK5 pathway in HT22 cells

  • Authors:
    • Xiu‑Yin Shen
    • Tao Luo
    • Sheng Li
    • Ou‑Yang Ting
    • Feng He
    • Jie Xu
    • Hua‑Qiao Wang
  • View Affiliations

  • Published online on: November 22, 2017     https://doi.org/10.3892/ijmm.2017.3281
  • Pages: 1138-1146
Metrics: Total Views: 0 (Spandidos Publications: | PMC Statistics: )
Total PDF Downloads: 0 (Spandidos Publications: | PMC Statistics: )


Abstract

Alzheimer's disease (AD) is a common neurodegenerative disorder characterized by aberrant tau protein hyperphosphorylation, which eventually leads to the formation of neurofibrillary tangles. Hyperphosphorylated tau protein is considered as a vital factor in the development of AD and is highly associated with cognitive impairment. Therefore, it is recognized to be a potential therapeutic target. Quercetin (QUE) is a naturally occurring flavonoid compound. In the present study, the inhibitory effect of QUE on okadaic acid (OA)-induced tau protein hyperphosphorylation in HT22 cells was explored. Western blotting results indicated that QUE significantly attenuated OA‑induced tau protein hyperphosphorylation at the Ser396, Ser199, Thr231 and Thr205 sites. Further experiments demonstrated that QUE inhibited the activity of cyclin‑dependent kinase 5 (CDK5), a key enzyme in the regulation of tau protein, and blocked the Ca2+‑calpain‑p25‑CDK5 signaling pathway. These observations indicate the ability of QUE to decrease tau protein hyperphosphorylation and thereby attenuate the associated neuropathology. In conclusion, these results support the potential of QUE as a therapeutic agent for AD and other neurodegenerative tauopathies.

Introduction

The incidence of Alzheimer's disease (AD) is gradually increasing, and AD has become a major threat to human health (1). Unfortunately, an effective treatment method has not yet been discovered (2,3). AD is a degenerative disease of the central nervous system. The deposition of extracellular amyloid plaques and the formation of intracellular neurofibrillary tangles (NFTs) are its primary pathological features. β-amyloid (Aβ), a cleavage product of the amyloid precursor protein, is the main component of amyloid plaques (46). Tau protein is a microtubule-associated protein closely involved in the maintenance of microtubule stability (7). Tau protein has numerous potential phosphorylation sites, which are mainly serine and threonine residues. The abnormal phosphorylation of tau protein reduces its affinity for microtubules and damages its microtubule assembly capacity (8,9). Furthermore, tau hyperphosphorylation is the dominating cause of the formation of NFTs (7,10). Although Aβ has been the principal focus of AD treatments, since tau phosphorylation has been indicated to be a consequence of Aβ pathology (11), the focus of attention has shifted from Aβ to tau protein (12).

The hyperphosphorylation of tau protein is mainly due to an increase in kinase activity and reduction of phosphatase activity (13,14). Among various kinases associated with this process, cyclin-dependent kinase 5 (CDK5) is considered to be particularly relevant (15). Abnormal CDK5 activity leads to the hyperphosphorylation of tau protein, which contributes to the formation of NFTs (16). A previous study indicated that CDK5 silencing decreased the number of NFTs in transgenic Alzheimer's mice (17). Notably, CDK5 is activated via subunits p35 or p39, and the cleavage of p35 to form p25 may occur due to the action of calpain, the activity of which is dependent upon calcium (1821). Compared with p35, p25 has a longer half-life; p25/CDK5-binding prolongs the activity of CDK5 and further promotes tau protein hyperphosphorylation, which serves an important role in the development of AD (22). Therefore, blocking the Ca2+-calpain-p25-CDK5 pathway has considerable significance for AD. A previous study has shown that A-705253, a calpain inhibitor, blocks stress-induced tau hyperphosphorylation (23). The restriction of CDK5 activity has an inhibitory effect on the aggregation of NFTs (17,23). In addition, a specific calpain inhibition, calpastatin, has demonstrated the ability to prevent tauopathy and neurodegeneration and restore a normal lifespan in tau P301L mice (24).

Quercetin (QUE) is a natural flavonoid compound that has been shown to exert extensive pharmacological effects, including antioxidant, antitumor, anti-inflammatory (2527), anti-chemotherapy-induced fatigue (28) and anti-aging effects (29). QUE has been demonstrated to cross the blood-brain barrier and prevent the progression of neurodegenerative diseases (3033). Numerous traditional Chinese medicines contain QUE, including Japanese pagoda tree flower, Apocynum venetum and cattail pollen (34,35). A previous study has indicated that QUE has the ability to reduce Aβ-induced cytotoxicity (36). Additionally, QUE has been revealed to attenuate tauopathy, although the mechanism has not been elucidated (37). Furthermore, QUE has been demonstrated to ameliorate AD pathology and protect cognitive and emotional functions in vivo (38,39).

The hippocampus, an important brain structure, is responsible for the strengthening of short-term memories into long-term memories and is closely relevant to AD (40). Okadaic acid (OA) is widely used to block protein phosphatase 2A (PP2A) activity (41,42). PP2A serves a vital role in in the development of neurodegenerative disorders via the hyperphosphorylation of tau protein (43,44). Therefore, OA-induced HT22 mouse hippocampal neuronal cells were selected for use in the present study as a model of AD. The effect of QUE pretreatment on tau protein hyperphosphorylation in OA-induced HT22 cells was investigated and the involvement of the Ca2+-calpain-p25-CDK5 signaling pathway in the underlying mechanism was evaluated. Natural compounds with fewer side effects are increasingly favored, which have lower toxicity and higher efficacy (45). The present study continues previous studies conducted by the current research team concerning the neuroprotective effects of other natural compounds (46,47).

Materials and methods

Materials

QUE (molecular formula, C15H1007; molecular weight, 302.24 g/mol; purity, >98.5%; CAS no., 117-39-5) was obtained from Aladdin Industrial Corporation (Shanghai, China). Calpeptin (CALP; CAS no., 117591-20-5), roscovitine (ROS; CAS no., 186692-46-6) and OA (molecular formula, C44H68O13; molecular weight, 805.00 g/mol; purity, >90%; CAS no., 78111-17-8) were all from Sigma-Aldrich (Merck KGaA, Darmstadt, Germany). Fluo-3 AM (S1056), Super ECL Plus (P1010) and a bicinchoninic acid (BCA) protein assay kit (P0010) were obtained from Beyotime Institute of Biotechnology (Jiangsu, China). Primary antibodies targeting CDK5 (ab40773), calpain-1 (ab28258), tau-5 (ab80579), tau [pS396] (ab32057) and tau [pT231] (ab15559) were from Abcam (Cambridge, UK). Tau-1 primary antibody (MAB3420) was from EMD Millipore (Billerica, MA, USA). Primary antibodies for tau [pS199] (44734G) and tau [pT205] (44738G) were from Invitrogen (Thermo Fisher Scientific, Inc., Waltham, MA, USA). Primary antibodies for p35/p25 (C64B10) and β-actin (13E5) were from Cell Signaling Technology, Inc. (Danvers, MA, USA). The primary antibody for p-CDK5 (Tyr15) (sc-12918) was from Santa Cruz Biotechnology, Inc. (Dallas, TX, USA). The horseradish peroxidase (HRP)-conjugated secondary antibody was from Wuhan Boster Biological Technology, Ltd. (BA1088; Wuhan, China).

Cell culture

The HT22 cells were a generous gift from Dr Jun Liu of the Memorial Hospital of Sun Yat-sen University (Guangzhou, China) (48). The HT22 cells were grown in a humidified incubator with 5% CO2 and 95% air at 37°C in Dulbecco's modified Eagle's medium (Hyclone DMEM; GE Healthcare Life Sciences, Logan, UT, USA) supplemented with 10% fetal bovine serum, 100 U/ml penicillin and 100 µg/ml streptomycin (all Gibco; Thermo Fisher Scientific, Inc.).

Cell treatment

The HT22 cells were grown in 6-well plate. OA was dissolved in DMSO to a concentration of 1 µM as a stock solution. The stock solution was diluted with DMEM to 80 nM prior to use. When the cell density reached 80%, the cells were incubated with QUE (5 or 10 µM), CALP (10 µM) or ROS (0.16 µM) for 24 h prior to exposure to OA (80 nM) for 12 h at 37°C.

Western blotting

HT22 cells were harvested following the treatments described above and lysed in ice-cold lysis buffer [1X PBS, 1% NP-40, 0.1% sodium dodecyl sulfate (SDS), 5 mM EDTA, 0.5% sodium deoxycholate and 1% phenylmethane sulfonyl fluoride] supplemented with phosphatase inhibitor for 30 min. The lysate was centrifuged at 14,000 × g for 20 min at 4°C. The supernatant was collected and its protein content was quantified using the BCA protein assay kit. Samples with equal amounts of protein (40 µg) were separated using 10% SDS-PAGE. The proteins were then transferred to polyvinylidene fluoride membranes. the membranes were blocked with 5% bovine serum albumin (Sigma-Aldrich) dissolved in 20 ml TBS with 1 ml Tween-20 buffer for 1 h at room temperature. Subsequently, the membranes were incubated overnight at 4°C with primary antibodies against CDK5 (1:2,000), p-CDK5 (1:1,000), tau-5 (1:1,000), tau-1 (1:10,000), tau [pS199] (1:1,000), tau [pT205] (1:1,000), tau [pS396] (1:1,000), tau [pT231] (1:1,000), calpain-1 (1:1,000), p35/p25 (1:1,000) and β-actin (1:1,000). Following this, the membranes were incubated with secondary HRP-conjugated antibody (1:10,000) at room temperature for 1 h. Immunoreactive proteins were detected using Super ECL Plus and exposed to X-ray films. ImageJ 1.410 software (National Institutes of Health, Bethesda, MD, USA) was used to quantitatively analyze the expression levels of the target proteins.

Reverse transcription-polymerase chain reaction (RT-PCR)

Total RNA was extracted from the HT22 cells in 6-well plates using TRIzol reagent (Thermo Fisher Scientific, Inc.). Spectrophotometry at 260 nm was conducted to determine the amount of RNA extracted. The primers used were as follows: p35 forward, 5′-GCA ACG GTC CCA AAA GGC TT-3′ and reverse, 5′-ACA GCA AGA ACG CCA AGG ACA-3′; CDK5 forward, 5′-GCA TTG AGT TTG GGC ACG ACA-3′ and reverse, 5′-AAA ACC GGG AAA CCC ATG AGA-3′; β-actin forward, 5′-ATG CCA TCC TGC GTC TGG ACC TGGC-3′ and reverse, 5′-AGC ATT TGC GGT GCA CGA TGG AGGG-3′. These primers were described previously by Chen et al (49). Samples were reverse-transcribed in RT reaction buffer using 400 ng total RNA according to the manufacturer's protocol. The PCR was conducted with template, primers, The RT kit was from Takara Biotechnology Co., Ltd. (Dalian, China). GoTaq Green Master mix and RNase-free dH2O added to a volume of 50 µl. Amplification was carried out under the following conditions: Initial denaturation at 95°C for 2 min, denaturation at 95°C for 45 sec, annealing at 59°C for 45 sec, extension at 72°C for 1 min, and a final extension step of 72°C for 10 min. The number of PCR cycles was 35. The products were detected in 2% agarose/Tris-acetate-EDTA gels and stained with ethidium bromide for visualization by Syngene G:BOX F2 and GeneTools software.

Intracellular calcium measurement

Intracellular calcium was determined by means of flow cytometry following the staining of the cells with the calcium indicator Fluo-3 AM. Following the various treatments, the cells were collected and cultured with 5 µM Fluo-3 AM at 37°C in the absence of light for 45 min. Cell fluorescence was then measured by flow cytometry. When the cell density reached 80%, the cells were incubated with QUE (5 or 10 µM), for 24 h prior to exposure to OA (80 nM) for 12 h at 37°C.

Statistical analysis

Data are presented as the mean ± standard error of the mean. Statistical significance was determined by one-way analysis of variance followed by Duncan's multiple range test using a computerized statistical package (SPSS 16.0). P<0.05 was considered to indicate a statistically significant difference. All experiments were repeated at least three times.

Results

Effects of QUE on OA-induced toxicity in HT22 cells

The control HT22 cells grew in a healthy condition, with the cell bodies exhibiting good translucency and clear boundaries (Fig. 1A). However, following the exposure of the cells to 80 nM OA for 12 h, cell growth was inhibited, the number of cells was markedly reduced, and the intercellular spaces appeared to be widened (Fig. 1B). Pretreatment with QUE (5 or 10 µM), the calpain inhibitor CALP (10 µM) or the CDK5 inhibitor ROS (0.16 µM) improved the cell morphology and increase the numbers of the OA-treated HT22 cells (Fig. 1C–F).

Effects of QUE on OA-induced tau protein hyperphosphorylation in HT22 cells

Tau protein hyperphosphorylation serves a very important role in AD and is a typical pathological feature of this disease (50). Therefore, the effects of QUE on OA-induced tau protein hyperphosphorylation were investigated. Western blotting demonstrated that tau protein hyperphosphorylation at four sites (S199, T205, T231 and S396) was significantly increased following the exposure of HT22 cells to OA (80 nM) for 12 h. However, these increases in phosphorylation were significantly attenuated to varying degrees by pretreatment with 5 or 10 µM QUE for 24 h (Fig. 2A and B). In addition, total tau protein and non-phosphorylated tau protein were also investigated. As shown in Fig. 2C and D, total tau protein (tau-5) did not vary significantly among the control, OA and OA plus QUE treatment groups, and the changes in the levels of non-phosphorylated tau (tau-1) were the converse of those for phosphorylated tau, which confirms the consistency of the results.

In order to study the effect of QUE on baseline tau protein phosphorylation, tau phosphorylation levels in HT22 cells cultured with QUE alone were detected (Fig. 2E and F). However, treatment with QUE culture exhibited no significant effect on tau phosphorylation compared with that in the untreated control group.

CDK5 is vital for tau protein hyperphosphorylation; the augmentation of intracellular Ca2+ levels leads to increased CDK5 activity, which consequently results in tau protein hyperphosphorylation (51). As shown in Fig. 2A and B, tau protein hyperphosphorylation was significantly reduced by pretreatment with 10 µM CALP or 0.16 µM ROS for 24 h. Furthermore, as shown in Fig. 2C and D, the effects of CALP and ROS on unphosphorylated tau protein in OA-treated HT22 cells were the converse of those on phosphorylated tau, and no significant changes in total tau protein were detected.

These results indicate that QUE markedly attenuated tau protein hyperphosphorylation in OA-induced HT22 cells via the Ca2+-calpain-p25-CDK5 signaling pathway, and indicate that QUE may exhibit a neuroprotective effect. However, QUE exhibited no effect on normal HT22 cells.

Effects of QUE on the OA-induced cleavage of p35

To investigate whether the Ca2+-calpain-p25-CDK5 signaling pathway is associated with the effects of QUE on OA-induced tau protein hyperphosphorylation, the changes of p25, p35 and CDK5 in OA-induced HT22 cells were explored. As shown in Fig. 3, p35 and CDK5 levels exhibited no significant difference among the groups. However, p25 was significantly increased following treatment with OA for 12 h, and this effect was significantly attenuated via pretreatment with QUE. These results indicate that QUE decreased the conversion of p35 into p25.

Effects of QUE on OA-induced p-CDK5 expression

p-CDK5, the active form of CDK5, is involved in the aggregation of phosphorylated tau protein (52). Therefore, the expression of p-CDK5 in the OA-induced HT22 cells was investigated. As shown in Fig. 4, p-CDK5 expression was increased significantly following exposure to OA for 12 h. However, this increase was significantly attenuated by pretreatment with 5 or 10 µM QUE, or 0.16 µM ROS for 24 h. These results are in accordance with the variations in p25 expression, and suggest that QUE reduced tau protein hyperphosphorylation by attenuating the cleavage of p35 and downregulating CDK5 activity.

Effects of QUE on OA-induced calpain expression

As p35 is converted to p25 by calpain, a calcium-dependent protease, the possibility that QUE may affect calpain expression was investigated. As shown in Fig. 5, calpain expression was significantly augmented following treatment with OA for 12 h. However, this increase was significantly attenuated by pretreatment with 5 or 10 µM QUE or 10 µM CALP for 24 h. These results indicate that QUE inhibited tau protein hyperphosphorylation, which was associated with a reduction of calpain expression.

Effects of QUE on OA-induced p35 and CDK5 mRNA

To further study the mechanism by which QUE decreased tau protein hyperphosphorylation via the CDK5 signaling pathway, the expression of p35 and CDK5 mRNA was examined. The exposure of HT22 cells to OA caused a significant increase in p35 mRNA, which was significantly blocked by pretreatment with 5 or 10 µM QUE. However, treatment with OA alone or with QUE pretreatment exhibited no significant effect on CDK5 mRNA (Fig. 6).

Effects of QUE on the OA-induced intracellular Ca2+ level

Calcium influx activates calpain, which has been reported as a factor in AD pathogenesis (18). Fig. 7 indicates that exposing HT22 cells to OA (80 nM) for 12 h caused a significant increase in intracellular Ca2+ levels. This increase was significantly attenuated by pretreatment with 5 or 10 µM QUE.

Discussion

Hyperphosphorylated tau protein is an essential component of NFTs, which are a major pathological factor in AD (12). Thus, tau protein hyperphosphorylation is a potential therapeutic target. Furthermore, it has been reported that tau pathology has a greater effect than amyloid burden on the clinical symptoms associated with AD; magnetic resonance imaging and electroencephalography indicate that Aβ deposition is relevant to functional network destruction whereas hyperphosphorylated tau directly affects memory deficits and cognition (53). Therefore, the inhibition of tau protein hyperphosphorylation is an important aim in AD. The present study provides evidence that QUE defended HT22 cells from OA-induced neurotoxicity by reducing tau protein hyperphosphorylation. During the study, it was observed that QUE reduced OA-induced tau protein hyperphosphorylation at Ser396, Ser199, Thr231 and Thr205 sites. However, no evident difference between 5 and 10 µM QUE was observed, with the exception of the Thr231 site, where QUE (10 µM) exhibited a stronger effect. Additionally, CALP and ROS, which are specific inhibitors of calpain and CDK5, respectively, decreased OA-induced tau protein hyperphosphorylation. Furthermore, none of the treatments affected the total tau levels. However, unphosphorylated tau levels were reduced by treatment with OA alone, and the reduction was attenuated by pretreatment with QUE, CALP or ROS. These results indicate that QUE effectively reduced tau hyperphosphorylation without changing the levels of total tau protein.

The aberrant phosphorylation of tau due to overactivated CDK5 activity is considered a major pathological mechanism in the development of AD (54). CDK5 serves as an upstream signaling molecule in the regulation of tau protein hyperphosphorylation, and is an important determinant of the state of tau protein (20). Therefore, downregulating CDK5 kinase activity is a potential target for AD. In the present study, whether the effect of QUE on hyperphosphorylated tau is attributable to downregulated CDK5 kinase activity was investigated. CDK5 activation was further examined by detecting the phosphorylation of CDK5 at Tyr15, which represents the activity of CDK5. Western blotting results demonstrated that the phosphorylation of CDK5-Tyr15 was attenuated by pretreatment with QUE or ROS. This indicates that QUE affected the activity of CDK5, and demonstrates the potential of QUE as a CDK5 inhibitor for use in AD.

As mentioned above, CDK5 activity is dependent on the p35 or p39 subunits of the enzyme, and the former can be cleaved to form p25. Therefore, CDK5 activity may be blocked by decreasing p35 or p25, which should consequently reduce tau protein hyperphosphorylation. Thus, the expression of p35, p25 and CDK5 was investigated in HT22 cells following exposure to OA. OA caused a significant increase in p25 levels, and pretreatment with QUE blocked the conversion of p35 to p25, leading to a reduction of hyperphosphorylated tau protein levels. Notably, the expression of CDK5 exhibited no difference among the groups. Based on these results, it may be concluded that QUE restrained OA-induced tau hyperphosphorylation by inhibiting the cleavage of p35 to p25 without affecting CDK5 expression. Additionally, the cleavage of p35 to p25 requires calpain, which is activated by intracellular calcium (55,56). To better explain the molecular mechanism by which QUE attenuated tau protein hyperphosphorylation, calpain expression was explored in the present study. Calpain expression was significantly increased following exposure to OA. However, this increase was attenuated by pretreatment with QUE. The positive control, CALP, also reduced calpain expression. Furthermore, intracellular calcium levels were evaluated, and the changes observed were in accordance with those for calpain. These findings demonstrate that QUE inhibited the OA-induced increases in calpain expression and intracellular calcium levels. Furthermore, the results indicate that QUE blocked the Ca2+-calpain-p25-CDK5 signaling pathway, ,and thus may be an effective treatment for AD.

To further elucidate the molecular mechanism by which QUE modulates the Ca2+-calpain-p25-CDK5 signaling pathway, p35 and CDK5 mRNA levels were detected. Notably, only p35 mRNA exhibited any changes when different treatments were applied. Thus, it appears that QUE reduced CDK5 activity by inhibiting the expression of p35, thereby decreasing the conversion of p35 to p25. This demonstrates that p35 mRNA is an effective target for QUE. Together, the results indicate that QUE acted on various targets in the Ca2+-calpain-p25-CDK5 signaling pathway to downregulate tau protein hyperphosphorylation.

In conclusion, the results of the present study suggest that QUE exhibited a marked neuroprotective effect on OA-induced HT22 cells by inhibiting the hyperphosphorylation of tau protein, and this effect may have been mediated via inhibition of the Ca2+-calpain-p25-CDK5 signaling pathway. This demonstrates that QUE is a potential therapeutic candidate for the prevention of tau protein hyperphosphorylation. Collectively, these findings expand our knowledge of the neuroprotective mechanism of QUE. However, the present study was restricted to in vitro experiments, and future studies to investigate the effect of QUE on transgenic mouse are planned. These may support the use of QUE as an effective therapeutic agent for AD and other tauopathies.

Acknowledgments

The present study was supported by the National Key Development Program for Basic Research of China (grant no. 2006cb500700), Medical Scientific Research Foundation of Guangdong Province (grant no. A2015032), Fundamental Research Funds for the Central Universities of China (grant no. 14ykpy03), National Natural Science Foundation of China (grant nos. 81774099 and 81173577) National Natural Science Foundation of China (grant no. 81501093), Natural Science Foundation of Guangdong Province (grant nos. 2015A030313066 and 2015A030310251) and Science and Technology Planning Project of Guangdong Province (grant no. 2014A020212622).

Glossary

Abbreviations

Abbreviations:

AD

Alzheimer's disease

NFTs

neurofibrillary tangles

QUE

quercetin

CDK5

cyclin-dependent kinase 5

β-amyloid

OA

okadaic acid

CALP

calpeptin

ROS

roscovitine

References

1 

Prince M, Bryce R and Ferri CA: World Alzheimer Report 2011: The Benefits of Early Diagnosis and Intervention. Alzheimer's Disease International; London: pp. 1–72. 2011

2 

Bassil N and Grossberg GT: Novel regimens and delivery systems in the pharmacological treatment of Alzheimer's disease. CNS Drugs. 23:293–307. 2009. View Article : Google Scholar : PubMed/NCBI

3 

Neugroschl J and Sano M: An update on treatment and prevention strategies for Alzheimer's disease. Curr Neurol Neurosci Rep. 9:368–376. 2009. View Article : Google Scholar : PubMed/NCBI

4 

Ballatore C, Lee VM and Trojanowski JQ: Tau-mediated neurodegeneration in Alzheimer's disease and related disorders. Nat Rev Neurosci. 8:663–672. 2007. View Article : Google Scholar : PubMed/NCBI

5 

Giacobini E and Becker RE: One hundred years after the discovery of Alzheimer's disease. A turning point for therapy? J Alzheimers Dis. 12:37–52. 2007. View Article : Google Scholar : PubMed/NCBI

6 

Pallàs M and Camins A: Molecular and biochemical features in Alzheimer's disease. Curr Pharm Des. 12:4389–4408. 2006. View Article : Google Scholar : PubMed/NCBI

7 

Takashima A: Tau aggregation is a therapeutic target for Alzheimer's disease. Curr Alzheimer Res. 7:665–669. 2010. View Article : Google Scholar : PubMed/NCBI

8 

Gong CX and Iqbal K: Hyperphosphorylation of micro-tubule-associated protein tau: A promising therapeutic target for Alzheimer disease. Curr Med Chem. 15:2321–2328. 2008. View Article : Google Scholar

9 

Iqbal K, Liu F, Gong CX and Grundke-Iqbal I: Tau in Alzheimer disease and related tauopathies. Curr Alzheimer Res. 7:656–664. 2010. View Article : Google Scholar : PubMed/NCBI

10 

Alonso AC, Mederlyova A, Novak M, Grundke-Iqbal I and Iqbal K: Promotion of hyperphosphorylation by frontotemporal dementia tau mutations. J Biol Chem. 279:34873–34881. 2004. View Article : Google Scholar

11 

Zheng WH, Bastianetto S, Mennicken F, Ma W and Kar S: Amyloid beta peptide induces tau phosphorylation and loss of cholinergic neurons in rat primary septal cultures. Neuroscience. 115:201–211. 2002. View Article : Google Scholar : PubMed/NCBI

12 

Giacobini E and Gold G: Alzheimer disease therapy - moving from amyloid-β to tau. Nat Rev Neurol. 9:677–686. 2013. View Article : Google Scholar : PubMed/NCBI

13 

Stoothoff WH and Johnson GV: Tau phosphorylation: physiological and pathological consequences. Biochim Biophys Acta. 1739:280–297. 2005. View Article : Google Scholar

14 

Wang JZ, Grundke-Iqbal I and Iqbal K: Kinases and phosphatases and tau sites involved in Alzheimer neurofibrillary degeneration. Eur J Neurosci. 25:59–68. 2007. View Article : Google Scholar : PubMed/NCBI

15 

Engmann O and Giese KP: Crosstalk between Cdk5 and GSK3β: Implications for Alzheimer's disease. Front Mol Neurosci. 2:22009. View Article : Google Scholar

16 

Tsai LH, Lee MS and Cruz J: Cdk5, a therapeutic target for Alzheimer's disease? Biochim Biophys Acta. 1697:137–142. 2004. View Article : Google Scholar : PubMed/NCBI

17 

Piedrahita D, Hernández I, López-Tobón A, Fedorov D, Obara B, Manjunath BS, Boudreau RL, Davidson B, Laferla F, Gallego-Gómez JC, et al: Silencing of CDK5 reduces neurofibrillary tangles in transgenic Alzheimer's mice. J Neurosci. 30:13966–13976. 2010. View Article : Google Scholar : PubMed/NCBI

18 

Angelo M, Plattner F and Giese KP: Cyclin-dependent kinase 5 in synaptic plasticity, learning and memory. J Neurochem. 99:353–370. 2006. View Article : Google Scholar : PubMed/NCBI

19 

Alvarez A, Muñoz JP and Maccioni RB: A Cdk5-p35 stable complex is involved in the beta-amyloid-induced deregulation of Cdk5 activity in hippocampal neurons. Exp Cell Res. 264:266–274. 2001. View Article : Google Scholar : PubMed/NCBI

20 

Noble W, Olm V, Takata K, Casey E, Mary O, Meyerson J, Gaynor K, LaFrancois J, Wang L, Kondo T, et al: Cdk5 is a key factor in tau aggregation and tangle formation in vivo. Neuron. 38:555–565. 2003. View Article : Google Scholar : PubMed/NCBI

21 

Utreras E, Maccioni R and González-Billault C: Cycl-in-dependent kinase 5 activator p35 over-expression and amyloid beta synergism increase apoptosis in cultured neuronal cells. Neuroscience. 161:978–987. 2009. View Article : Google Scholar : PubMed/NCBI

22 

Dhavan R and Tsai LH: A decade of CDK5. Nat Rev Mol Cell Biol. 2:749–759. 2001. View Article : Google Scholar : PubMed/NCBI

23 

Nikkel AL, Martino B, Markosyan S, Brederson JD, Medeiros R, Moeller A and Bitner RS: The novel calpain inhibitor A-705253 prevents stress-induced tau hyperphosphorylation in vitro and in vivo. Neuropharmacology. 63:606–612. 2012. View Article : Google Scholar : PubMed/NCBI

24 

Rao MV, McBrayer MK, Campbell J, Kumar A, Hashim A, Sershen H, Stavrides PH, Ohno M, Hutton M and Nixon RA: Specific calpain inhibition by calpastatin prevents tauopathy and neurodegeneration and restores normal lifespan in tau P301L mice. J Neurosci. 34:9222–9234. 2014. View Article : Google Scholar : PubMed/NCBI

25 

Orsolić N, Knezević AH, Sver L, Terzić S and Basić I: Immunomodulatory and antimetastatic action of propolis and related polyphenolic compounds. J Ethnopharmacol. 94:307–315. 2004. View Article : Google Scholar

26 

Gulati N, Laudet B, Zohrabian VM, Murali R and Jhanwar-Uniyal M: The antiproliferative effect of quercetin in cancer cells is mediated via inhibition of the PI3K-Akt/PKB pathway. Anticancer Res. 26(2A): 1177–1181. 2006.PubMed/NCBI

27 

Landis-Piwowar KR, Milacic V and Dou QP: Relationship between the methylation status of dietary flavonoids and their growth-inhibitory and apoptosis-inducing activities in human cancer cells. J Cell Biochem. 105:514–523. 2008. View Article : Google Scholar : PubMed/NCBI

28 

Mahoney SE, Davis JM, Murphy EA, McClellan JL and Pena MM: Dietary quercetin reduces chemotherapy-induced fatigue in mice. Integr Cancer Ther. 13:417–424. 2014. View Article : Google Scholar : PubMed/NCBI

29 

Chondrogianni N, Kapeta S, Chinou I, Vassilatou K, Papassideri I and Gonos ES: Anti-ageing and rejuvenating effects of quercetin. Exp Gerontol. 45:763–771. 2010. View Article : Google Scholar : PubMed/NCBI

30 

Ferri P, Angelino D, Gennari L, Benedetti S, Ambrogini P, Del Grande P and Ninfali P: Enhancement of flavonoid ability to cross the blood-brain barrier of rats by co-administration with α-tocopherol. Food Funct. 6:394–400. 2015. View Article : Google Scholar

31 

Li Y, Zhou S, Li J, Sun Y, Hasimu H, Liu R and Zhang T: Quercetin protects human brain microvascular endothelial cells from fibrillar β-amyloid1-40-induced toxicity. Acta Pharm Sin B. 5:47–54. 2015. View Article : Google Scholar : PubMed/NCBI

32 

Ishisaka A, Mukai R, Terao J, Shibata N and Kawai Y: Specific localization of quercetin-3-O-glucuronide in human brain. Arch Biochem Biophys. 557:11–17. 2014. View Article : Google Scholar : PubMed/NCBI

33 

Faria A, Pestana D, Teixeira D, Azevedo J, De Freitas V, Mateus N and Calhau C: Flavonoid transport across RBE4 cells: a blood-brain barrier model. Cell Mol Biol Lett. 15:234–241. 2010. View Article : Google Scholar : PubMed/NCBI

34 

Li H, Liu Y, Yi Y, Miao Q, Liu S, Zhao F, Cong W, Wang C and Xia C: Purification of quercetin-3-O-sophoroside and isoquercitrin from Poacynum hendersonii leaves using macroporous resins followed by Sephadex LH-20 column chromatography. J Chromatogr B Analyt Technol Biomed Life Sci. 1048:56–63. 2017. View Article : Google Scholar : PubMed/NCBI

35 

Zhang SH, Wang SQ, Liu CH and Yang YH: Studies on quality standards for Pollen Typhae(puhuang). Zhongguo Zhong Yao Za Zhi. 25:136–139. 2000.In Chinese.

36 

Ansari MA, Abdul HM, Joshi G, Opii WO and Butterfield DA: Protective effect of quercetin in primary neurons against Aβ(1-42): relevance to Alzheimer's disease. J Nutr Biochem. 20:269–275. 2009. View Article : Google Scholar

37 

Rezai-Zadeh K, Arendash GW, Hou H, Fernandez F, Jensen M, Runfeldt M, Shytle RD and Tan J: Green tea epigallo-catechin-3-gallate (EGCG) reduces beta-amyloid mediated cognitive impairment and modulates tau pathology in Alzheimer transgenic mice. Brain Res. 1214:177–187. 2008. View Article : Google Scholar : PubMed/NCBI

38 

Devi L and Ohno M: 7,8-Dihydroxyflavone, a small-molecule TrkB agonist, reverses memory deficits and BACE1 elevation in a mouse model of Alzheimer's disease. Neuropsychopharmacology. 37:434–444. 2012. View Article : Google Scholar :

39 

Spencer JP: The impact of flavonoids on memory: physiological and molecular considerations. Chem Soc Rev. 38:1152–1161. 2009. View Article : Google Scholar : PubMed/NCBI

40 

Oishi K and Lyketsos CG: Alzheimer's disease and the fornix. Front Aging Neurosci. 6:2412014. View Article : Google Scholar : PubMed/NCBI

41 

Shi Y: Serine/threonine phosphatases: Mechanism through structure. Cell. 139:468–484. 2009. View Article : Google Scholar : PubMed/NCBI

42 

Sun L, Liu SY, Zhou XW, Wang XC, Liu R, Wang Q and Wang JZ: Inhibition of protein phosphatase 2A- and protein phosphatase 1-induced tau hyperphosphorylation and impairment of spatial memory retention in rats. Neuroscience. 118:1175–1182. 2003. View Article : Google Scholar : PubMed/NCBI

43 

Bennecib M, Gong CX, Grundke-Iqbal I and Iqbal K: Inhibition of PP-2A upregulates CaMKII in rat forebrain and induces hyperphosphorylation of tau at Ser 262/356. FEBS Lett. 490:15–22. 2001. View Article : Google Scholar : PubMed/NCBI

44 

Martin L, Latypova X, Wilson CM, Magnaudeix A, Perrin ML and Terro F: Tau protein phosphatases in Alzheimer's disease: The leading role of PP2A. Ageing Res Rev. 12:39–49. 2013. View Article : Google Scholar

45 

Tao T, He C, Deng J, Huang Y, Su Q, Peng M, Yi M, Darko KO, Zou H and Yang X: A novel synthetic derivative of quercetin, 8-trifluoromethyl-3,5,7,3′,4′-O-pentamethyl-quercetin, inhibits bladder cancer growth by targeting the AMPK/mTOR signaling pathway. Oncotarget. 8:71657–71671. 2017.PubMed/NCBI

46 

Luo T, Jiang W, Kong Y, Li S, He F, Xu J and Wang HQ: The protective effects of jatrorrhizine on β-amyloid(25–35)-induced neurotoxicity in rat cortical neurons. CNS Neurol Disord Drug Targets. 11:1030–1037. 2012. View Article : Google Scholar : PubMed/NCBI

47 

Luo T, Zhang H, Zhang WW, Huang JT, Song EL, Chen SG, He F, Xu J and Wang HQ: Neuroprotective effect of Jatrorrhizine on hydrogen peroxide-induced cell injury and its potential mechanisms in PC12 cells. Neurosci Lett. 498:227–231. 2011. View Article : Google Scholar : PubMed/NCBI

48 

Liu J, Li L and Suo WZ: HT22 hippocampal neuronal cell line possesses functional cholinergic properties. Life Sci. 84:267–271. 2009. View Article : Google Scholar : PubMed/NCBI

49 

Chen X, Huang T, Zhang J, Song J, Chen L and Zhu Y: Involvement of calpain and p25 of CDK5 pathway in ginsenoside Rb1's attenuation of β-amyloid peptide25–35-induced tau hyperphosphorylation in cortical neurons. Brain Res. 1200:99–106. 2008. View Article : Google Scholar : PubMed/NCBI

50 

Wang JZ, Wang ZH and Tian Q: Tau hyperphosphorylation induces apoptotic escape and triggers neurodegeneration in Alzheimer's disease. Neurosci Bull. 30:359–366. 2014. View Article : Google Scholar : PubMed/NCBI

51 

Shukla V, Seo J, Binukumar BK, Amin ND, Reddy P, Grant P, Kuntz S, Kesavapany S, Steiner J, Mishra SK, Tsai LH and Pant HC: TFP5, a peptide inhibitor of aberrant and hyperactive Cdk5/p25, attenuates pathological phenotypes and restores synaptic function in CK-p25Tg mice. J Alzheimers Dis. 56:335–349. 2017. View Article : Google Scholar : PubMed/NCBI

52 

Zukerberg LR, Patrick GN, Nikolic M, Humbert S, Wu CL, Lanier LM, Gertler FB, Vidal M, Van Etten RA and Tsai LH: Cables links Cdk5 and c-Abl and facilitates Cdk5 tyrosine phosphorylation, kinase upregulation, and neurite outgrowth. Neuron. 26:633–646. 2000. View Article : Google Scholar : PubMed/NCBI

53 

Pievani M, de Haan W, Wu T, Seeley WW and Frisoni GB: Functional network disruption in the degenerative dementias. Lancet Neurol. 10:829–843. 2011. View Article : Google Scholar : PubMed/NCBI

54 

Kimura T, Ishiguro K and Hisanaga S: Physiological and pathological phosphorylation of tau by Cdk5. Front Mol Neurosci. 7:652014. View Article : Google Scholar : PubMed/NCBI

55 

Kawahara M and Kuroda Y: Intracellular calcium changes in neuronal cells induced by Alzheimer's beta-amyloid protein are blocked by estradiol and cholesterol. Cell Mol Neurobiol. 21:1–13. 2001. View Article : Google Scholar : PubMed/NCBI

56 

Kusakawa G, Saito T, Onuki R, Ishiguro K, Kishimoto T and Hisanaga S: Calpain-dependent proteolytic cleavage of the p35 cyclin-dependent kinase 5 activator to p25. J Biol Chem. 275:17166–17172. 2000. View Article : Google Scholar : PubMed/NCBI

Related Articles

Journal Cover

February-2018
Volume 41 Issue 2

Print ISSN: 1107-3756
Online ISSN:1791-244X

Sign up for eToc alerts

Recommend to Library

Copy and paste a formatted citation
x
Spandidos Publications style
Shen XY, Luo T, Li S, Ting OY, He F, Xu J and Wang HQ: Quercetin inhibits okadaic acid-induced tau protein hyperphosphorylation through the Ca2+‑calpain‑p25‑CDK5 pathway in HT22 cells. Int J Mol Med 41: 1138-1146, 2018.
APA
Shen, X., Luo, T., Li, S., Ting, O., He, F., Xu, J., & Wang, H. (2018). Quercetin inhibits okadaic acid-induced tau protein hyperphosphorylation through the Ca2+‑calpain‑p25‑CDK5 pathway in HT22 cells. International Journal of Molecular Medicine, 41, 1138-1146. https://doi.org/10.3892/ijmm.2017.3281
MLA
Shen, X., Luo, T., Li, S., Ting, O., He, F., Xu, J., Wang, H."Quercetin inhibits okadaic acid-induced tau protein hyperphosphorylation through the Ca2+‑calpain‑p25‑CDK5 pathway in HT22 cells". International Journal of Molecular Medicine 41.2 (2018): 1138-1146.
Chicago
Shen, X., Luo, T., Li, S., Ting, O., He, F., Xu, J., Wang, H."Quercetin inhibits okadaic acid-induced tau protein hyperphosphorylation through the Ca2+‑calpain‑p25‑CDK5 pathway in HT22 cells". International Journal of Molecular Medicine 41, no. 2 (2018): 1138-1146. https://doi.org/10.3892/ijmm.2017.3281