Inhibitors of Leucine Rich Repeat Kinase 2 (LRRK2) Protect Against LRRK2-Models of Parkinson’s Disease

Neuroregeneration Program, Institute for Cell Engineering, Department of Neurology, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA.
Nature medicine (Impact Factor: 28.05). 09/2010; 16(9):998-1000. DOI: 10.1038/nm.2199
Source: PubMed

ABSTRACT Leucine-rich repeat kinase-2 (LRRK2) mutations are a common cause of Parkinson's disease. Here we identify inhibitors of LRRK2 kinase that are protective in in vitro and in vivo models of LRRK2-induced neurodegeneration. These results establish that LRRK2-induced degeneration of neurons in vivo is kinase dependent and that LRRK2 kinase inhibition provides a potential new neuroprotective paradigm for the treatment of Parkinson's disease.

Download full-text


Available from: Howard Federoff, Jul 05, 2015
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: LRRK2IN1 is a highly potent inhibitor of leucine-rich repeat kinase 2 (LRRK2, IC50 = 7.9 nM), an established target for treatment of Parkinson's disease. Two LRRK2IN1 analogues 1 and 2 were synthesised which retained LRRK2 inhibitory activity (1: IC50 = 72 nM; 2: IC50 = 51 nM), were predicted to have improved bioavailability and were efficacious in cell-based models of neuroinflammation. Analogue 1 inhibited IL-6 secretion from LPS-stimulated primary human microglia with EC50 = 4.26 μM. In order to further optimize the molecular properties of LRRK2IN1, a library of truncated analogues was designed based on docking studies. Despite lacking LRRK2 inhibitory activity, these compounds show anti-neuroinflammatory efficacy at micromolar concentration. The compounds developed were valuable tools in establishing a cell-based assay for assessing anti-neuroinflammatory efficacy of LRRK2 inhibitors. Herein, we present data that IL-1β stimulated U87 glioma cell line is a reliable model for neuroinflammation, as data obtained in this model were consistent with results obtained using primary human microglia and astrocytes. Copyright © 2015 Elsevier Masson SAS. All rights reserved.
    European Journal of Medicinal Chemistry 05/2015; 95. DOI:10.1016/j.ejmech.2015.03.003 · 3.43 Impact Factor
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: Leucine-rich repeat kinase 2 (LRRK2) is a complex, multidomain protein which is considered a valuable target for potential disease-modifying therapeutic strategies for Parkinson’s disease. In mammalian cells and brain, LRRK2 is phosphorylated and treatment of cells with inhibitors of LRRK2 kinase activity can induce LRRK2 dephosphorylation at a cluster of serines including Ser910/935/955/973. It has been suggested that phosphorylation levels at these sites reflect LRRK2 kinase activity, however kinase-dead variants of LRRK2 or kinase activating variants do not display altered Ser935 phosphorylation levels compared to wild type. Furthermore, Ser910/935/955/973 are not autophosphorylation sites, therefore, it is unclear if inhibitor induced dephosphorylation depends on the activity of compounds on LRRK2 or on yet to be identified upstream kinases. Here we used a panel of 160 ATP competitive and cell permeable kinase inhibitors directed against all branches of the kinome and tested their activity on LRRK2 in vitro using a peptide-substrate-based kinase assay. In neuronal SH-SY5Y cells overexpressing LRRK2 we used compound-induced dephosphorylation of Ser935 as readout. In silico docking of selected compounds was performed using a modelled LRRK2 kinase structure. Receiver operating characteristic plots demonstrated that the obtained docking scores to the LRRK2 ATP binding site correlated with in vitro and cellular compound activity. We also found that in vitro potency showed a high degree of correlation to cellular compound induced LRRK2 dephosphorylation activity across multiple compound classes. Therefore, acute LRRK2 dephosphorylation at Ser935 in inhibitor treated cells results from compound activity on the LRRK2 ATP-binding pocket itself. Understanding the regulation of LRRK2 phosphorylation by kinase inhibitors aids our understanding of LRRK2 signaling and may lead to development of new classes of LRRK2 kinase inhibitors.
    Frontiers in Molecular Neuroscience 05/2014; 7:51. DOI:10.3389/fnmol.2014.00051
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: Mutations in LRRK2 are one of the primary genetic causes of Parkinson's disease (PD). LRRK2 contains a kinase and a GTPase domain, and familial PD mutations affect both enzymatic activities. However, the signaling mechanisms regulating LRRK2 and the pathogenic effects of familial mutations remain unknown. Identifying the signaling proteins that regulate LRRK2 function and toxicity remains a critical goal for the development of effective therapeutic strategies. In this study, we apply systems biology tools to human PD brain and blood transcriptomes to reverse-engineer a LRRK2-centered gene regulatory network. This network identifies several putative master regulators of LRRK2 function. In particular, the signaling gene RGS2, which encodes for a GTPase-activating protein (GAP), is a key regulatory hub connecting the familial PD-associated genes DJ-1 and PINK1 with LRRK2 in the network. RGS2 expression levels are reduced in the striata of LRRK2 and sporadic PD patients. We identify RGS2 as a novel interacting partner of LRRK2 in vivo. RGS2 regulates both the GTPase and kinase activities of LRRK2. We show in mammalian neurons that RGS2 regulates LRRK2 function in the control of neuronal process length. RGS2 is also protective against neuronal toxicity of the most prevalent mutation in LRRK2, G2019S. We find that RGS2 regulates LRRK2 function and neuronal toxicity through its effects on kinase activity and independently of GTPase activity, which reveals a novel mode of action for GAP proteins. This work identifies RGS2 as a promising target for interfering with neurodegeneration due to LRRK2 mutations in PD patients.
    Human Molecular Genetics 05/2014; DOI:10.1093/hmg/ddu202 · 6.68 Impact Factor