Novel para-phenyl substituted diindolylmethanes protect against MPTP neurotoxicity and suppress glial activation in a mouse model of Parkinson's disease
Document Type
Article
Abstract
The orphan nuclear receptor NR4A2 (Nurr1) constitutively regulates inflammatory gene expression in glial cells by suppressing DNA binding activity of NF-κB. We recently reported that novel 1,1-bis(3'-indolyl)-1-(p-substitutedphenyl)methane (C-DIM) compounds that activate NR4A family nuclear receptors in cancer lines also suppress inflammatory gene expression in primary astrocytes and prevent loss of dopaminergic neurons in mice exposed to 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine and probenecid (MPTPp). In this study, we postulated that the basis for this neuroprotection involves blockade of glial activation and subsequent expression of NF-κB-regulated inflammatory genes. To examine this mechanism, we treated transgenic NF-κB/EGFP reporter mice with MPTPp for 7 days (MPTPp7d) followed by daily oral gavage with either vehicle (corn oil; MPTPp14d) or C-DIMs containing p-methoxyphenyl (C-DIM5), p-hydroxyphenyl (C-DIM8), or p-chlorophenyl (C-DIM12) groups. Each compound conferred significant protection against progressive loss of dopaminergic neurons in the substantia nigra pars compacta (SNpc), even when given after 7 days of dosing with MPTPp. C-DIM12 had the greatest neuroprotective activity in MPTPp-treated mice, and was also the most potent compound in suppressing activation of microglia and astrocytes, expression of cytokines and chemokines in quantitative polymerase chain reaction (qPCR) array studies, and in reducing expression of NF-κB/EGFP in the SN. C-DIM12 prevented nuclear export of Nurr1 in dopaminergic neurons and enhanced expression of the Nurr1-regulated proteins tyrosine hydroxylase and the dopamine transporter. These data indicate that NR4A-active C-DIM compounds protect against loss of dopamine neurons in the MPTPp model of PD by preventing glial-mediated neuronal injury and by supporting a dopaminergic phenotype in TH-positive neurons in the SNpc.
Keywords
Parkinson’s disease, microglia, neuroinflammation, orphan nuclear receptors
Medical Subject Headings
Animals; Anisoles (chemistry, pharmacology, therapeutic use); Antiparkinson Agents (chemistry, pharmacology, therapeutic use); Behavior, Animal (drug effects); Cell Count; Dopaminergic Neurons (drug effects, pathology); Green Fluorescent Proteins (genetics); Indoles (chemistry, pharmacology, therapeutic use); MPTP Poisoning (metabolism, pathology, prevention & control); Mice, Transgenic; NF-kappa B (genetics); Neuroglia (drug effects, metabolism); Parkinson Disease (metabolism, pathology, prevention & control); Phenols (chemistry, pharmacology, therapeutic use)
Publication Date
2-1-2015
Publication Title
Toxicological sciences : an official journal of the Society of Toxicology
E-ISSN
1096-0929
Volume
143
Issue
2
First Page
360
Last Page
73
PubMed ID
25406165
Digital Object Identifier (DOI)
10.1093/toxsci/kfu236
Recommended Citation
De Miranda, Briana R.; Popichak, Katriana A.; Hammond, Sean L.; Miller, James A.; Safe, Stephen; and Tjalkens, Ronald B., "Novel para-phenyl substituted diindolylmethanes protect against MPTP neurotoxicity and suppress glial activation in a mouse model of Parkinson's disease" (2015). Translational Neuroscience. 2550.
https://scholar.barrowneuro.org/neurobiology/2550