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The antidiabetic drug troglitazone protects against PrP (106‑126)‑induced neurotoxicity via the PPARγ‑autophagy pathway in neuronal cells

  • Authors:
    • Ji-Hong Moon
    • Jeong-Min Hong
    • Sang-Youel Park
  • View Affiliations

  • Published online on: April 7, 2021     https://doi.org/10.3892/mmr.2021.12069
  • Article Number: 430
  • Copyright: © Moon et al. This is an open access article distributed under the terms of Creative Commons Attribution License.

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Abstract

Prion diseases, which involve the alteration of cellular prion protein into a misfolded isoform, disrupt the central nervous systems of humans and animals alike. Prior research has suggested that peroxisome proliferator‑activator receptor (PPAR)γ and autophagy provide some protection against neurodegeneration. PPARs are critical to lipid metabolism regulation and autophagy is one of the main cellular mechanisms by which cell function and homeostasis is maintained. The present study examined the effect of troglitazone, a PPARγ agonist, on autophagy flux in a prion peptide (PrP) (106‑126)‑mediated neurodegeneration model. Western blot analysis confirmed that treatment with troglitazone increased LC3‑II and p62 protein expression, whereas an excessive increase in autophagosomes was verified by transmission electron microscopy. Troglitazone weakened PrP (106‑126)‑mediated neurotoxicity via PPARγ activation and autophagy flux inhibition. A PPARγ antagonist blocked PPARγ activation as well as the neuroprotective effects induced by troglitazone treatment, indicating that PPARγ deactivation impaired troglitazone‑mediated protective effects. In conclusion, the present study demonstrated that troglitazone protected primary neuronal cells against PrP (106‑126)‑induced neuronal cell death by inhibiting autophagic flux and activating PPARγ signals. These results suggested that troglitazone may be a useful therapeutic agent for the treatment of neurodegenerative disorders and prion diseases.

Introduction

Transmissible spongiform encephalopathies (TSEs) are fatal neurodegenerative diseases caused by prions (1). TSEs have common pathognomonic and histopathological characteristics, including spongiform changes, glial proliferation, neuronal loss, and the deposition of a misfolded isoform (PrPsc) (2) of the cellular prion protein (PrPc). Whether the prion disease at issue is genetic, transmissible, or an irregular disorder, they all implicate protein refolding of the normal prion (PrPc), which is encoded by the Prnp gene (3). PrPsc, a misfolded version of PrPc, was originally thought to be an accumulated proteinase K-resistant prion protein. However, patients with PrPc could still incur disease-related and diagnostically imperative alterations even without its conversion to the protease-resistant form (4).

Synthetic human prion peptide (PrP) (106–126) preserves some features of PrPsc's physiological and pathogenic assets and can initiate apoptosis of hippocampal neurons (5). An investigation of the respective amino acid sectors showed that the peptide, including amino acids 106–126 of the PrP sequence, was able to replicate several biological features of PrPsc in vitro, including amyloidogenesis, as well as its neurotoxic and its gliotrophic effects (68). Moreover, PrP (106–126) covers an AGAAAAGA arrangement at amino acids 113 to 120, a motif that has been found in PrP molecules across numerous species (9).

Troglitazone is an antidiabetic medicine used to treat type 2 diabetes, improve the sensitivity of various tissues to insulin, and reduce blood glucose levels (1012). Troglitazone's antidiabetic effects are closely related to peroxisome proliferator-activated receptor (PPAR)γ activation, which suggests that it is the activation of PPAR-responsive genes that is responsible for the insulin-sensitizing effects of troglitazone (1315). PPARγ is a member of the class of PPARs that are associated with ligand-stimulated nuclear receptors (16). PPARγ is primarily expressed in adipose tissue and plays an important role in lipid metabolism alteration, insulin sensitivity, and adipocyte differentiation (17,18). Some studies have proposed that PPARγ activation has a protective effect on neuronal cells and inhibits neurodegeneration (1922). With this in mind, we investigated whether troglitazone protected against prion peptide-mediated neuronal apoptosis.

Autophagy, also known as programmed cell death-II, is a homeostatic and catabolic progression by which cellular constituents and organelles are delivered to lysosomes for degradation (23,24). Autophagy begins with the development of double-membrane structures (autophagosomes) that enclose cellular ingredients and organelles. Once these are combined with lysosomes, they progress to a maturing system and, ultimately resulting in the collapse and recycling of the cargo (25,26). p62 levels correlate with autophagy (27). While p62 is selectively degraded by autolysosomal degradation, it is not degraded by the ubiquitin-proteasome system (UPS) (28). p62 levels increase when autophagy is repressed (29,30).

In our prior research, we uncovered that the inhibition of autophagy prevented PrP (106–126)-mediated neuronal cytotoxicity (31). In this study, we investigate whether troglitazone protects against PrP (106–126)-mediated neuronal cytotoxicity via autophagy flux and whether the autophagy flux is controlled by PPARγ.

Materials and methods

Cell culture

Embryonic 18-day ICR mice were purchased from SAMTAKO (Osan, Korea). No experiments were performed on live animals. The animals were euthanized by cervical dislocation and the brain was collected from the pups. Primary murine cortex neuron culture was performed according to the protocol of Beaudoin et al (32) and a little modified. Brain was dissected in Hanks Buffered Saline Solution without Mg2+ and Ca2+ (HBSS: Gibco; Thermo Fisher Scientific, Inc.) and digested in 0.25% trypsin containing DNAse I (2,000 U/mg) (Gibco; Thermo Fisher Scientific, Inc.) for 20 min at 37°C. The obtained cell suspension was diluted in DMEM containing 25 mM glucose and 10% fetal bovine serum (FBS), and then cultured in tissue culture flasks coated with 50 µg/ml poly-D-lysine at a density of 3–4×105 cells/cm2. The SK-N-SH (human neuroblastoma cell line, passage no. 14) was acquired from the American Type Culture Collection (ATCC). SK-N-SH cells were cultured in Minimum Essential Medium (Hyclone Laboratories) with 10% fetal bovine serum (FBS, Gibco; Thermo Fisher Scientific, Inc.) and gentamycin (0.1 mg/ml) at 37°C and 5% CO2.

Chemical and PrP (106–126) treatment

Synthetic prion peptides PrP (106–126) (Lys-Thr-Asn-Met-Lys-His-Met-Ala-Gly-Ala-Ala-Ala-Ala-Gly-Ala-Val-Val-Gly-Gly-Leu-Gly) were manufactured by Peptron. The peptides were dissolved in sterile dimethyl sulfoxide (DMSO) at a stock concentration of 10 mM and stored at −20°C.

The stock solution of troglitazone (8 mM; Sigma-Aldrich; Merck KGaA) was dissolved in DMSO. The cells were pre-incubated with 20, 40, or 80 µM troglitazone with/without PrP (100 µM) for 12 h. For the inhibitor treatments, the cultures were pretreated with a 10 µM CQ (autophagy inhibitor; Sigma-Aldrich) or 10 µM GW9662 (PPARγ antagonist; Sigma-Aldrich; Merck KGaA).

Trypan blue exclusion assay

Cell viability was evaluated by trypan blue exclusion assay using a hemocytometer. Untreated cells were used as the control group and cell viability was compared with the control. Each treatment was performed in triplicate.

Annexin V/PI assay

Cells in the logarithmic phase were collected and cultured in 24-well plates at 4×104 cells/well. Cell survival was evaluated using an Annexin V/PI Assay Kit (Santa Cruz Biotechnology) following the manufacturer's procedure. Briefly, cells were treated for 24 h and then harvested, washed in cold phosphate-buffered saline (PBS) twice and then stained with fluorescein isothiocyanate (FITC)-conjugated Annexin V and PI dyes. The externalization of phosphatidylserine and the permeability to PI were evaluated using a flow cytometer. Data from 5,000 gated events per sample were collected. Cells in early stages of apoptosis were positively stained with Annexin V, whereas cells in late apoptosis were positively stained with both Annexin V and PI. The fluorescence was determined at 488 nm excitation and 525/30 emission using a Guava EasyCyte HT System (Millipore).

Terminal deoxynucleotidyl transferase dUTP nick end-labeling (TUNEL) assay

Cells in the logarithmic phase were collected and cultured in 6-well plates at 3×105 cells/well. Neuronal apoptosis was assessed after treatment using an ApoBrdU DNA Fragmentation Assay Kit (BioVision), following the manufacturer's instructions. The nuclei were counterstained with PI.

RNA interference

SK-N-SH cells were transfected with ATG5 small-interfering RNA (siRNA; oligoID HSS114104; Invitrogen; Thermo Fisher Scientific, Inc.) using Lipofectamine 2000 according to the manufacturer's instructions. After a 48-h culture, knockdown efficiency was measured at the protein level by immunoblot analysis. Nonspecific siRNA (oligoID 12935-300; Invitrogen; Thermo Fisher Scientific, Inc.) was used as the negative control.

BacMam transduction

GFP-LC3B puncta assay was evaluated in neuronal cells using the virus from the Premo Autophagy Sensor LC3B-GFP (BacMam 2.0) kit (Life Technologies, P36235). LC3B-FP and LC3B (G120A)-FP viral vectors (MOI, 30) were employed to monitor autophagosome dynamics by fluorescence microscopy analysis.

Immunocytochemistry

Cells in the logarithmic phase were collected and cultured on 1% gelatin-coated coverslips (12 mm; Nalge Nunc International) in 24-well plates at 4×104 cells/well. After treatment, the cells were fixed with 4% PFA in PBS (1X) at pH 7.4 for 20 min at room temperature (RT). The cells were washed in sterile Tris-buffered saline TBS (1M), 3 g Tris (24.8 mM), 8 g NaCl (137 mM), and 0.2 g KCl (2.7 mM) in 1 liter distilled water at pH 7.4 with 0.1% Tween-20 (TBST) for 10 min. They were then blocked for 15 min in TBST with 5% FBS, and incubated for 3 h at RT with the primary antibodies (anti-PPARγ diluted 1:1,000; sc-7273; Santa Cruz Biotechnology), which had themselves been diluted in TBST with 5% FBS. Alexa Fluor 488-labeled donkey anti-rabbit IgG antibody (A21206; Molecular Probes) diluted 1:1,000 was employed to visualize the channel expression using fluorescence microscopy (Nikon Eclipse 80i). The images were evaluated using NIS-Elements F Ver4.60 imaging software.

Confocal microscopy

After being subjected to either immunocytochemistry or the GFP-LC3B puncta assay, the coverslips were placed in mounting medium and imaged through a 63× oil objective on a Zeiss LSM710 microscope equipped with a standard set of lasers. The excitation wavelengths were 488, 543, and 633 nm. The bandpass filters were set at 500–550 (AlexaFluor488), 560–615 nm (Cy3, AlexaFluor568), and 650–750 nm (AlexaFluor647).

Western blot analysis

Cells in the logarithmic phase were collected and cultured in 6-well plates at 3×105 cells/well. After the treatments, the cells were washed with PBS and lysed in lysis buffer [25 mM HEPES (4-(2-hydroxyethyl)-1-piperazineethanesulfonic acid) at pH 7.4, 100 mM NaCl, 1 mM ethylenediaminetetraacetic acid (EDTA), 5 mM MgCl2, 0.1 mM dithiothreitol (DTT), and a protease inhibitor mixture]. Equal quantities of cellular proteins (15–30 µg/µl) were electrophoretically resolved on a 10% sodium dodecyl sulfate (SDS) polyacrylamide gel and transferred to a nitrocellulose membrane. Immunoreactivity was detected through consecutive incubations with a blocking solution containing 5% skim milk and primary antibodies followed by the corresponding horseradish peroxidase-conjugated secondary antibodies, and finally developed using enhanced chemiluminescence substances in the WESTSAVE Gold Detection Kit (LF-QC0103; AbFrontier Inc.). The primary antibodies, anti-PPARγ diluted 1:1,000 (sc-7273; Santa Cruz Biotechnology), anti-LC3B diluted 1:1,000 (#4108; Cell Signaling Technology), anti-P62 diluted 1:1,000 (#5114; Cell Signaling Technology) and anti-β-actin diluted 1:5,000 (A5441; Sigma-Aldrich; Merck KGaA), in the antibody solution (1% skim milk in TBST) were used for immunoblotting. The images were inspected using a Fusion FX7 imaging system (Vilber Lourmat, Torcy Z.I. Sud). The density of the signal bands was evaluated using Bio-1D software (Vilber Lourmat).

Transmission electron microscopy (TEM) analysis

The cells for TEM were fixed in 2% glutaraldehyde [Electron Microscopy Sciences (EMS)] and 2% paraformaldehyde (EMS) in 0.05 M sodium cacodylate (pH 7.2; EMS) for 2 h at 4°C. The samples were fixed in 1% osmium tetroxide (EMS) for 1 h at 4°C, dehydrated with a graded ethanol series (25, 50, 70, 90 and 100%) for 5 min each, and embedded in epoxy resin (Embed 812; EMS) for 48 h at 60°C following to the manufacturer's instructions. Ultrathin sections (60 nm) were cut using an LKB-III Ultratome (Leica Microsystems GmbH) and stained with 0.5% uranyl acetate (EMS) for 20 min and 0.1% lead citrate (EMS) for 7 min at RT. The fluorescent images were recorded on a Hitachi H7650 electron microscope (Hitachi, Ltd.; magnification, ×10,000) installed at the Center for University-Wide Research Facilities (CURF) at Jeonbuk National University.

Statistical analysis

Results are expressed as the means ± standard deviations (SD) from at least three independent replicates. All experiments were analyzed by the one-way analysis of variance. Comparisons of three or more groups were made using Tukey's post hoc test. All statistical analyses were implemented with GraphPad Prism version 5.0 software. P<0.05 was considered to indicate a statistically significant difference.

Results

Protective effect of troglitazone on prion protein-mediated neuronal cell death

Consistent with the relevant literature (33,34) and our preliminary experiments, we used different concentrations of troglitazone for efficacy testing. We selected 80 µM troglitazone as highest concentration because it significantly increased cell viability (at 100 µM PrP). Once our preliminary experiments were complete, we proceeded to examine the effect of troglitazone on PrP (106–126)-mediated neurotoxicity by an Annexin V/PI assay in primary neuronal cells. Cells were treated with PrP in combination with troglitazone. PrP treatment led to a 2.25-fold decrease in cell viability (Annexin V/PI) compared to the control. In detail, PrP treatment increased early apoptosis (Annexin V+/PI) from about 2% to about 30% and late apoptosis (Annexin V+/PI+) from about 1% to about 19%. We observed that pretreatment with troglitazone dose-dependently protected neurons against PrP (106–126)-induced neurotoxicity. Treatment of the cells with 20, 40, and 80 µM troglitazone increased cell viability by 1.18±1.20 (SD), 1.34±1.19 (SD), and 1.70±1.23 (SD)-fold, respectively, compared to PrP-treated cells (Fig. 1A and B). In addition, we confirmed the protective effect of 80 µM troglitazone in SK-N-SH cells (data not shown). Consistent with this, in the trypan blue assay, troglitazone repressed PrP-mediated cell death dose-dependently (Fig. 1C). Troglitazone also decreased DNA strand damage triggered by PrP treatment (Fig. 1D and E). These results indicate that troglitazone attenuated PrP (106–126)-mediated neuronal cell death.

Troglitazone restrains autophagy flux in neuronal cells

It has traditionally been thought that LC3 and SQSTM1/p62 are consumed by lysosomal degradation via the process of autophagy flux (28). We found that LC3-II and SQSTM1/p62 protein levels were increased in the troglitazone-treated groups. Treatment of the cells with 80 µM troglitazone increased SQSTM1/p62 protein level by 2.44±0.50-fold compared to the control (Fig. 2A and B). The BacMam 2.0 system was employed to observe the construction of autophagosomes in the neuroblastoma cells. Troglitazone led to an increase in punctate fluorescence in SK-N-SH cells (Fig. 2C and D). The observed punctate fluorescence distribution pattern suggested that the LC3B-FP protein was collected in the autophagosomes. Using transmission electron microscopy (TEM), we observed that troglitazone treatment improved phagophore accumulation that was not degraded by the lysosomes (Fig. 2E and F), suggesting that troglitazone inhibited autophagy flux in neuronal cells. To demonstrate the effect of autophagy inhibition on PrP-mediated neuronal cell death, we performed cell viability assays using Annexin V/propidium iodide (PI) with/without chloroquine (CQ). We chose the CQ concentration on the basis of other studies (35,36). We confirmed that, like the CQ autophagy inhibitor, troglitazone had neuroprotective effects via autophagy inhibition (Fig. 3A and B). We also found that troglitazone and CQ increased levels of p62 and LC3B-II protein (Fig. 3C and D), suggesting an inhibition of autophagy flux. On the basis of the observation that p62 protein level and cell viability did not increase by more when troglitazone and CQ were treated together, we propose that troglitazone and CQ play the same role in inhibiting autophagy flux.

Moreover, the Atg5 knockdown had little impact on troglitazone-mediated neuroprotection (Fig. 4A and B) and inhibition of autophagy flux (Fig. 4C and D). Specifically, troglitazone repressed autophagy flux and PrP-mediated neuronal apoptosis by inhibiting fusion between the autophagosome and the lysosome, not by reduction of Atg5. We confirmed the successful siRNA transfection of ATG5 through additional experiments; the results revealed that Atg5 siRNA reduced the expression levels of Atg5 and LC3B, and increased p62 (Fig. S1). These experimental results indicate that troglitazone or Atg5 knockdown result in an inhibition of autophagy flux, and thereby exert a neuroprotective effect in an in vitro prion model.

PPARγ activation by troglitazone attenuates PrP (106–126)-mediated neuronal cell death via inhibition of autophagy flux

We evaluated whether troglitazone-activated PPARγ weakened prion peptide-mediated neuronal cell death by inhibiting autophagy flux. Troglitazone dose-dependently increased the activation of PPARγ, as indicated by the red fluorescence in Fig. 5C and D. Treatment of the cells with 80 µM troglitazone increased PPARγ protein levels by 3.74±0.60-fold compared to the control (Fig. 5A and B). PPARγ antagonist GW9662, which was employed at a concentration consistent with previous studies (37,38), suppressed PPARγ activation. Moreover, increased LC3-II and p62 protein expression, which indicates the inhibition of autophagy flux, was reversed by the PPARγ antagonist (Fig. 6A and B). These experiments demonstrate that troglitazone-induced inhibition of autophagy flux is regulated by PPARγ. To investigate the effect of PPARγ activation on PrP-mediated neurotoxicity, we performed cell viability experiments with and without the PPARγ antagonist. We determined that troglitazone's neuroprotective effect was inhibited by the PPARγ antagonist (Fig. 6C and D). This data collectively provides a strong basis for our conclusion that PPARγ activation by troglitazone prevents PrP (106–126)-mediated neurotoxicity by inhibiting autophagy flux.

Discussion

The purpose of this study was to investigate whether troglitazone could be a potential agent for targeting PPARγ and autophagy flux, thereby decreasing prion protein-mediated neuronal cell death. Our findings confirm troglitazone's potential as a therapeutic agent in response to neurodegenerative diseases, including prion diseases. We suggest that the PPARγ signaling and autophagy flux affected by troglitazone might be a strategic mechanism to target in prion disease.

Nah et al (39) reported that the Prnp gene activates autophagy in response to the presence of amyloid-β in neuronal cells. A number of studies have theorized that autophagy generates cellular apoptosis (4043). These studies underlie our assumption that the amyloid plaque formed by PrPsc accumulates and stimulates neuronal autophagic cell death. In a previous study, we determined that human prion peptide 106–126 stimulated acute autophagy flux to promote autophagic cell death in neurons and that CQ attenuated PrP-induced neurotoxicity via autophagy inhibition (31). In this study, we determined that autophagy inhibition by troglitazone could protect neuronal cells against PrP-induced cell death. Troglitazone inhibited PrP-mediated autophagic cell death, and the addition of CQ had no change on the protective effect (Fig. 3). As co-treatment with troglitazone and CQ resulted in no synergic effect, that the inference to be drawn is that troglitazone inhibited autophagic signals. This result was further affirmed in our tests using Atg5 siRNA tools (Fig. 4).

We explored upstream of the troglitazone- induced neuronal autophagy flux. Troglitazone, a PPARγ agonist, suppresses the excretion of inflammatory cytokines and neurotoxic agents from stimulated monocytes and microglia, and thus has anti-inflammatory properties (4446). We determined that troglitazone stimulated PPARγ activation, which in turn regulated PrP-mediated autophagic cell death.

The anti-inflammatory functions of PPARγ have recently received a great deal of attention, as its agonists have been shown to exert protective effects in neurologic diseases (4749). Some studies have reported that PPARγ ligands protect against the oxidative stress in neuronal injury (5052), while others have suggested that PPARγ activation may obstruct autophagy flux (5355). In this paper, we demonstrated that troglitazone activated PPARγ in neurons and used a PPARγ inhibitor to prevent PrP-mediated autophagic cell death (Figs. 5 and 6). These findings suggest that troglitazone-activated PPARγ protected neuronal cells against PrP-induced cell death via autophagy inhibition. Previous studies suggested several materials, such as resveratrol, could prevent prion-induced neurotoxicity (56,57). This is the first study indicating that troglitazone-mediated PPARγ may play a critical role in the neuroprotection against PrP (106–126)-induced neurotoxicity.

Similar to PrPsc, a neurotoxic prion protein segment, PrP (106–126), preserves biochemical substances, such as protease resistance, β-sheet formation, and cytotoxicity (6,5860). Some studies have investigated prion pathogenesis and neurotoxic pathways in vivo using Rocky Mountain Laboratory (RML) infection and antibody-derived anti-PrP ligands (6163). In these studies, the neurodegenerative changes typical of prion diseases were observed without detectable PrPsc, suggesting the presence of additional mechanisms of neuronal death in prion disorders, aside from those related to PrPsc (64,65). We suggest that prion peptide may have valuable role as a therapeutic strategy for prion diseases though PrP (106–126) is not equivalent to PrPsc. We found that the 106–126 sequence of the prion protein is an efficient model for in vitro study of prion-induced cell death, as it results in rapid depolarization of mitochondrial membranes. Based on these observations, it was suggested that PrP (106–126) is a major contributor to the physicochemical and pathogenic properties of PrPsc. Although the function and mechanism of prion protein are still obscure, numerous studies have suggested that prior formation of prions are initiated by accumulation of PrPsc in the brain, analogous to amyloid-β in Alzheimer's disease (6668).

Prior research has suggested that chemical drugs or plant extracts protect neurons during autophagy in neurodegenerative disease (6973). The biological role of autophagy in neurodegenerative diseases, however, is debated. Nah et al (39) have suggested that abnormal autophagy could be induced by amyloid-β or accumulation of misfolded prion proteins in neuronal cells. In this study, we limited ourselves to experiments with PrP (106–126) in neuronal cells, not animal models. Accordingly, the prion peptide's autophagic effects have yet to be demonstrated in vivo, and further studies will be needed to discover whether prion peptide induces the neurotoxic effect that occurs during autophagy in mice models.

Most experiments were conducted using primary neuronal cells. In some experiments, SK-N-SH neuroblastoma cells were used (as described in the figure legends) as it proved difficult to observe fluorescent proteins in primary neuronal cells were, the cells was crushed and their shape destroyed, and as cells could no longer be propagated once they were terminally differentiated into mature neurons (74). SK-N-SH neuroblastoma cells, as the parental line of SH-SY5Y, have been widely used to characterize neuron-like behavior when investigating potential neuroprotective activity in in vitro models (74,75).

To obtain an understanding of their interplay, we examined the impact of troglitazone treatment on PrP-induced cell death, PPARγ, and autophagy flux in neuronal cells. This study revealed that PrP-mediated autophagic cell death could be prevented by troglitazone via neuronal PPARγ activation. Based on this study, regulating autophagy flux may be an effective means of mitigating the damage caused by prion diseases. Further studies could determine optimal strategies for the modulation of ROS for neurodegeneration treatment as ROS may be involved in both autophagy flux and prion diseases.

Supplementary Material

Supporting Data

Acknowledgements

Not applicable.

Funding

This study was supported by a Korean Grant from the National Research Foundation (NRF) funded by the Ministry of Education (grant no. 2019R1A2B5B02069765) and ‘Research Base Construction Fund Support Program’ funded by Jeonbuk National University in 2020.

Availability of data and materials

The datasets used and/or analyzed during the current study are available from the corresponding author on reasonable request.

Authors' contributions

JHM, JMH and SYP designed and executed the study, analyzed the data and wrote the manuscript. JHM and SYP confirm the authenticity of all the raw data. All authors read and approved the final manuscript.

Ethics approval and consent to participate

This project received approval from the Institutional Review Board of Jeonbuk National University (approval no. CBNU-2019-00113).

Patient consent for publication

Not applicable.

Competing interests

The authors declare that they have no competing interests.

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Volume 23 Issue 6

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Spandidos Publications style
Moon J, Hong J and Park S: The antidiabetic drug troglitazone protects against PrP (106‑126)‑induced neurotoxicity via the PPARγ‑autophagy pathway in neuronal cells. Mol Med Rep 23: 430, 2021
APA
Moon, J., Hong, J., & Park, S. (2021). The antidiabetic drug troglitazone protects against PrP (106‑126)‑induced neurotoxicity via the PPARγ‑autophagy pathway in neuronal cells. Molecular Medicine Reports, 23, 430. https://doi.org/10.3892/mmr.2021.12069
MLA
Moon, J., Hong, J., Park, S."The antidiabetic drug troglitazone protects against PrP (106‑126)‑induced neurotoxicity via the PPARγ‑autophagy pathway in neuronal cells". Molecular Medicine Reports 23.6 (2021): 430.
Chicago
Moon, J., Hong, J., Park, S."The antidiabetic drug troglitazone protects against PrP (106‑126)‑induced neurotoxicity via the PPARγ‑autophagy pathway in neuronal cells". Molecular Medicine Reports 23, no. 6 (2021): 430. https://doi.org/10.3892/mmr.2021.12069