Parkinson’s disease (PD) is a neurodegenerative disorder characterized by the loss of dopaminergic neurons in the Substantia Nigra pars compacta, leading to classical PD motor symptoms. Current therapies are purely symptomatic and do not modify disease progression. Cannabidiol (CBD), one of the main phytocannabinoids identified in Cannabis Sativa, which exhibits a large spectrum of therapeutic properties, including anti-inflammatory and antioxidant effects, suggesting its potential as disease-modifying agent for PD. The aim of this study was to evaluate the effects of chronic treatment with CBD (10 mg/kg, i.p.) on PD-associated neurodegenerative and neuroinflammatory processes, and motor deficits in the 6-hydroxydopamine model. Moreover, we investigated the potential mechanisms by which CBD exerted its effects in this model. CBD-treated animals showed a reduction of nigrostriatal degeneration accompanied by a damping of the neuroinflammatory response and an improvement of motor performance. In particular, CBD exhibits a preferential action on astrocytes and activates the astrocytic transient receptor potential vanilloid 1 (TRPV1), thus, enhancing the endogenous neuroprotective response of ciliary neurotrophic factor (CNTF). These results overall support the potential therapeutic utility of CBD in PD, as both neuroprotective and symptomatic agent.

Background GBA mutations are the commonest genetic risk factor for Parkinson's disease (PD) and also impact disease progression. Objective The objective of this study was to define a biochemical profile that could distinguish GBA‐PD from non‐mutated PD. Methods 29 GBA‐PD, 37 non‐mutated PD, and 40 controls were recruited; α‐synuclein levels in plasma, exosomes, and peripheral blood mononuclear cells were analyzed, GCase and main GCase‐related lysosomal proteins in peripheral blood mononuclear cells were measured. Results Assessment of plasma and exosomal α‐synuclein levels did not allow differentiation between GBA‐PD and non‐mutated PD; conversely, measurements in peripheral blood mononuclear cells clearly distinguished GBA‐PD from non‐mutated PD, with the former group showing significantly higher α‐synuclein levels, lower GCase activity, higher LIMP‐2, and lower Saposin C levels. Conclusion We propose peripheral blood mononuclear cells as an easily accessible and manageable model to provide a distinctive biochemical profile of GBA‐PD, potentially useful for patient stratification or selection in clinical trials. © 2021 The Authors. Movement Disorders published by Wiley Periodicals LLC on behalf of International Parkinson and Movement Disorder Society

Heterozygous mutations in the GBA gene, encoding the lysosomal enzyme glucocerebrosidase (GCase), are the strongest known genetic risk factor for Parkinson’s disease (PD). The molecular mechanisms underlying the increased PD risk and the variable phenotypes observed in carriers of different GBA mutations are not yet fully elucidated. Extracellular vesicles (EVs) have gained increasing importance in neurodegenerative diseases since they can vehiculate pathological molecules potentially promoting disease propagation. Accumulating evidence showed that perturbations of the endosomal–lysosomal pathway can affect EV release and composition. Here, we investigate the impact of GCase deficiency on EV release and their effect in recipient cells. EVs were purified by ultracentrifugation from the supernatant of fibroblast cell lines derived from PD patients with or without GBA mutations and quantified by nanoparticle tracking analysis. SH-SY5Y cells over-expressing alpha-synuclein (α-syn) were used to assess the ability of patient-derived small EVs to affect α-syn expression. We observed that defective GCase activity promotes the release of EVs, independently of mutation severity. Moreover, small EVs released from PD fibroblasts carrying severe mutations increased the intra-cellular levels of phosphorylated α-syn. In summary, our work shows that the dysregulation of small EV trafficking and alpha-synuclein mishandling may play a role in GBA-associated PD.

Background: Peptidase mitochondrial processing alpha (PMPCA) biallelic mutations cause a spectrum of disorders ranging from severe progressive multisystemic mitochondrial encephalopathy to a milder non-progressive cerebellar ataxia with or without intellectual disability. Recently, we and others described an intermediate phenotype in two unrelated patients. Methods: We report a second Italian patient carrying novel PMPCA variants (p.Trp278Leu; p.Arg362Gly). Molecular modeling, dynamics simulation, RT-qPCR, and Western blotting were performed to predict the pathogenic impact of variants in the two Italian patients and attempt genotype-phenotype correlates. Results: In line with the two patients with intermediate phenotypes, our case presented global psychomotor delay with regression, intellectual disability, spastic-ataxic gait, and hyperkinetic movements, with cerebellar atrophy and bilateral striatal hyperintensities. However, blood lactate, muscle biopsy, and MRI spectroscopy were normal. PMPCA protein levels were significantly higher than controls despite normal cDNA levels. Dynamics simulation of several PMPCA missense variants showed a variable impact on the flexibility of the glycine rich loop and, for some cases, on the overall protein stability, without clear genotype-phenotype correlates. Conclusion: We confirm the expansion of PMPCA phenotypic spectrum including an intermediate phenotype of progressive encephalopathy without systemic involvement. The association of cerebellar atrophy with “Leigh-like” striatal hyperintensities may represent a “red flag” for this condition.

This protocol details methods for the isolation of peripheral blood mononuclear cells (PBMCs) from Whole Blood