Neuroprotective effect of the chemical chaperone, trehalose in a chronic MPTP-induced Parkinson’s disease mouse model Sumit Sarkar a,1, *, Srinivasulu Chigurupati a,1 , James Raymick b , Dushyant Mann c , John F. Bowyer a , Tom Schmitt d , Richard D. Beger d , Joseph P. Hanig e , Larry C. Schmued a , Merle G. Paule a a Division of Neurotoxicology, National Center for Toxicological Research/FDA, Jefferson, AR 72079, United States b Toxicology Pathology Associates, Jefferson, AR 72079, United States c Wayne State University School of Medicine, Detroit, MI 48201, United States d Division of Systems Biology, National Center for Toxicological Research/FDA, Jefferson, AR 72079, United States e Office of Testing & Research, CDER/FDA, White Oak, MD 20993, United States 1. Introduction Parkinsonism is one of the most common chronic neurodegen- erative disorders that affect motor coordination. Degeneration of dopamine (DA) neurons located in the pars compacta of the substantia nigra and formation of Lewy bodies that contain ubiquitin and a-synuclein (Hornykiewicz, 2010) are two major hallmarks of the disease. The major symptoms commonly seen in PD patients are: tremor, rigidity, bradykinesia, poor balance and difficulty in walking. More than 80% of the DA synthesizing cells are typically lost in symptomatic PD individuals (Birkmayer and Hornykiewicz, 1961; Bjorklund and Finnveden, 2007; Hornykiewicz, 2006). Although the etiology and cellular mechanisms underlying PD are not well understood, therapeutic interventions are primarily limited to pharmacologically elevating striatal (caudate/putamen, CPu) DA levels or deep-brain electrical stimulation. In the present study, we investigated the role of trehalose in preventing, by a NeuroToxicology 44 (2014) 250–262 A R T I C L E I N F O Article history: Received 19 June 2014 Accepted 15 July 2014 Available online 23 July 2014 Keywords: Parkinson’s disease Endothelial cells Trehalose Tyrosine hydroxylase FT-gel A B S T R A C T Parkinson’s disease (PD) is a progressive motor disease of unknown etiology in the majority of cases. The clinical features of PD emerge due to selective degeneration of dopamine (DA) neurons in the substantia nigra pars compacta (SNc), which project to the caudate putamen (CPu) where they release DA. In the current in vivo mouse model study, we tested trehalose for its ability to protect against 1-methyl-4- phenyl-1,2,3,6-tetrahydropyridine (MPTP)-induced damage to DA neurons. Trehalose is a naturally occurring disaccharide present in plants and animals and appears capable of protecting cells against various environmental stresses. The effect of trehalose is likely due to its action as a pharmacological chaperone which promotes protein stability. In the present study, there were four treatment groups: saline only (control); probenecid only; MPTP + probenecid; and trehalose + MPTP + probenecid. MPTP- induced losses in tyrosine hydroxylase and DA transporter immunoreactivity in the ventral midbrain SNc and CPu were significantly reduced by trehalose. Decreases in CPu dopamine levels produced by MPTP were also blocked by trehalose. Microglial activation and astrocytic hypertrophy induced by MPTP were greatly reduced by trehalose, indicating protection against neuroinflammation. These effects are commensurate with the observed trehalose sparing of motor deficits produced by MPTP in this mouse model. Two tight junctional proteins, ZO-1 and occludin, are downregulated following MPTP treatment and trehalose blocks this effect. Likewise, the glucose transporter-1 that is expressed in brain endothelial cells is also protected by trehalose from MPTP-induced down-regulation. This study is the first to demonstrate using fluoro-turoquoise FT gel perfusion techniques, the protection afforded by trehalose from MPTP-induced damage to microvessels and endothelial and suggests that trehalose therapy may have the potential to slow or ameliorate PD pathology. Published by Elsevier Inc. * Corresponding author at: Division of Neurotoxicology, National Center for Toxicological Research/FDA, Bldg. 53D, HFT-32, Jefferson, AR 72079, United States. Tel.: +1 81335475201; fax: +1 81355652322. E-mail address: Sumit.Sarkar@FDA.hhs.gov (S. Sarkar). 1 These authors have equally contributed to this article. Contents lists available at ScienceDirect NeuroToxicology http://dx.doi.org/10.1016/j.neuro.2014.07.006 0161-813X/Published by Elsevier Inc.