Neuropeptide Y mitigates neuropathology and motor deficits in mouse models of Machado–Joseph disease

Abstract

Machado-Joseph disease (MJD) is a fatal, dominantly inherited neurodegenerative disorder associated with an expanded polyglutamine tract within the ataxin-3 protein, and characterized by progressive impairment of motor coordination, associated with neurodegeneration of specific brain regions, including cerebellum and striatum. The currently available therapies do not allow modification of disease progression. Neuropeptide Y (NPY) has been shown to exert potent neuroprotective effects by multiple pathways associated with the MJD mechanisms of disease. Thus, we evaluated NPY levels in MJD and investigated whether raising NPY by gene transfer would alleviate neuropathological and behavioural deficits in cerebellar and striatal mouse models of the disease. For that, a cerebellar transgenic and a striatal lentiviral-based models of MJD were used. NPY overexpression in the affected brain regions in these two mouse models was obtained by stereotaxic injection of adeno-associated viral vectors encoding NPY. Up to 8 weeks after viral injection, balance and motor coordination behaviour and neuropathology were analysed. We observed that NPY levels were decreased in two MJD patients' cerebella and in striata and cerebella of disease mouse models. Furthermore, overexpression of NPY alleviated the motor coordination impairments and attenuated the related neuropathological parameters, preserving cerebellar volume and granular layer thickness, reducing striatal lesion and decreasing mutant ataxin-3 aggregation. Additionally, NPY mediated increase of brain-derived neurotrophic factor levels and decreased neuroinflammation markers. Our data suggest that NPY is a potential therapeutic strategy for MJD.

Cerebellar Transcriptome Profiles of ATXN1 Transgenic Mice Reveal SCA1 Disease Progression and Protection Pathways

“…Thus, these results strongly support a model where elevated Cck and its subsequent processing to a peptide that binds to Purkinje cell Cck1R in an autocrine manner underlies the lack of progressive Purkinje cell pathology in ATXN1[30Q]D776 mice. A similar neuroprotective role for another neuropeptide NPY in mouse models of SCA3/MJD was recently reported by Duarte-Neves et al 2015. Elucidation of a Cck/Cck1R pathway as being protective against a progressive SCA1-like PC disease has potential therapeutic implications.…”

Effect of early embryonic deletion of huntingtin from pyramidal neurons on the development and long-term survival of neurons in cerebral cortex and striatum

“…The membranes were blocked in 5% non-fat milk in PBS for 1 h at room temperature and incubated overnight at 4 °C with mouse monoclonal antibody against huntingtin (Millipore MAB 2166, 1:3000), rabbit polyclonal against BDNF (Alomone labs ANT-010, 1:1000), rabbit monoclonal against Erk1/2 (Cell Signaling mAb 4695, 1:1000), rabbit monoclonal against phospho-Erk1/2 (Cell Signaling mAb 4370, 1:2000), rabbit polyclonal against phospho-Akt (Cell Signaling Ab 9271, 1:1000), or mouse monoclonal against beta-tubulin (Chemicon, MAB 3408, 1:5000). The specificity of these antibodies for their target antigens has been demonstrated by the manufacturer by Western blot and in published studies by others (Harrington et al, 2012; Milman and Woulfe, 2013; Czech et al, 2014; Duarte-Neves et al, 2015; Gu et al, 2017; Patel et al, 2017). The membranes were then washed in PBS containing 0.2% Tween, and incubated with anti-mouse or anti-rabbit secondary antibodies at room temperature for 1 h. The membranes were subsequently washed in PBS containing 0.2% Tween, and protein bands were visualized by chemiluminescence (Pierce, Rockford, IL) and autoradiography.…”

Gene therapy for the CNS using AAVs: The impact of systemic delivery by AAV9

“…Intraparenchymal injection has been the most commonly used route of administration of AAV vectors to the CNS by our group and others [60,61], as well as in the majority of clinical studies ( Table 2). The direct delivery into the brain parenchyma circumvents the blood-brain barrier (BBB), but leads to poor vector spread (1-3 mm), and as a result transgene expression is limited to the site of injection [62].…”