Mitochondrial dysfunction and oxidative stress occur in Parkinson's disease (PD), but the molecular mechanisms controlling these events are not completely understood. Peroxisome proliferator-activated receptor-gamma coactivator-1α (PGC-1α) is a transcriptional coactivator known as master regulator of mitochondrial functions and oxidative metabolism. Recent studies, including one from our group, have highlighted altered PGC-1α activity and transcriptional deregulation of its target genes in PD pathogenesis suggesting it as a new potential therapeutic target. Resveratrol, a natural polyphenolic compound proved to improve mitochondrial activity through the activation of several metabolic sensors resulting in PGC-1α activation. Here we have tested in vitro the effect of resveratrol treatment on primary fibroblast cultures from two patients with early-onset PD linked to different Park2 mutations. We show that resveratrol regulates energy homeostasis through activation of AMP-activated protein kinase (AMPK) and sirtuin 1 (SIRT1) and raise of mRNA expression of a number of PGC-1α's target genes resulting in enhanced mitochondrial oxidative function, likely related to a decrease of oxidative stress and to an increase of mitochondrial biogenesis. The functional impact of resveratrol treatment encompassed an increase of complex I and citrate synthase activities, basal oxygen consumption, and mitochondrial ATP production and a decrease in lactate content, thus supporting a switch from glycolytic to oxidative metabolism. Moreover, resveratrol treatment caused an enhanced macro-autophagic flux through activation of an LC3-independent pathway. Our results, obtained in early-onset PD fibroblasts, suggest that resveratrol may have potential clinical application in selected cases of PD-affected patients.

Stichting ParkinsonFonds, Dorpmans-Wigmans Stichting, Erasmus Medical Center, ZonMw-Memorabel programme, EU Joint Programme Neurodegenerative Disease Research (JPND), Parkinson's UK, Avtal om Läkarutbildning och Forskning (ALF) and Parkinsonfonden (Sweden), Lijf and Leven foundation, and cross-border grant of Alzheimer Netherlands-Ligue Européene Contre la Maladie d'Alzheimer (LECMA).

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Dementia is a frequent non-motor feature of Parkinson's disease (PD). Elevated plasma homocysteine (Hcy) levels have been associated with both cognitive impairment and dementia. Increased Hcy levels have been observed in levodopa-treated patients with PD. The objective of our study was to evaluate the association between plasma Hcy levels and dementia in PD. We performed a multicenter cross-sectional study on patients with PD with (PDD) and without (PDnD) dementia and age- and sex-matched healthy controls. We compared Hcy levels in patients with PDD and PDnD and healthy controls, and we performed logistic regression analysis to search for an association between the presence of dementia and increased Hcy levels in PD. Patients with PD (121), PDD (42), and PDnD (79), and age- and sex-matched controls (154) were enrolled. Hcy levels were higher in patients with PD compared to controls (17.5 micromol/L +/- 10.2 vs. 11 +/- 4.1; P < 0.00001). Among patients with PD, Hcy levels were higher in the PDD group compared to the PDnD group (20.7 micromol/L +/- 12.1 vs. 15.8 +/- 8.5; P = 0.002). In a multivariate logistic regression model, higher Hcy levels [Odds ratios comparing the top (>18.9 micromol/L) with the bottom tertile (<12.4 micromol/L): 3.68; 95% CI: 1.14-11.83] were significantly associated with dementia. These data support the association between elevated Hcy levels and the presence of dementia in PD.

Parkinson's disease (PD) is the most common neurodegenerative movement disorder caused primarily by selective degeneration of the dopaminergic neurons in substantia nigra. In this work the proteomes extracted from primary fibroblasts of two unrelated, hereditary cases of PD patients, with different parkin mutations, were compared with the proteomes extracted from commercial adult normal human dermal fibroblasts (NHDF) and primary fibroblasts from the healthy mother of one of the two patients. The results show that the fibroblasts from the two different cases of parkin-mutant patients display analogous alterations in the expression level of proteins involved in different cellular functions, like cytoskeleton structure-dynamics, calcium homeostasis, oxidative stress response, protein and RNA processing.

Our results raise the possibility that Hcy plays a role in the development of dyskinesias, through its toxic effects on both dopaminergic neurons and non-substantia nigra, non-dopaminergic neurons.

Introduction: We investigated the clinical differences between familial and sporadic frontotemporal dementia (FTD), screening for mutations in known FTD genes. Methods: We diagnosed 22 affected individuals belonging to 8 families and 43 sporadic cases with FTD in Apulia, Southern Italy in two years. Mutations in common causative FTD genes (GRN, MAPT, VCP and TARDBP) and C9ORF72 expansions were screened. Results: Behavioural variant of FTD was the most common clinical subtype (50% and 69% in familial and sporadic cases, respectively). Social conduct impairment/disinhibition, loss of insight, and inflexibility were the most frequent clinical features observed at onset. One new mutation was identified in GRN in family A. Conclusion: Disease onset in sporadic FTD was more frequently characterized by a clustering of behavioral symptoms with apathy and loss of personal hygiene. Mutations in common causative FTD genes are not a major cause of familial and sporadic FTD in the Southern Italian population.

Based on the available data, the possibility that the hyperhomocysteinemia may contribute to the pathogenesis of PD remains uncertain. L-dopa treatment represents the major determinant of the hyperhomocysteinemia observed in PD.