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Easily accessible biomarkers in Huntington disease (HD) are actively searched. We investigated telomere length and DNA double-strand breaks (histone variant pγ-H2AX) as predictive disease biomarkers in peripheral blood mononuclear cells (PBMC) from 25 premanifest subjects, 58 HD patients with similar CAG expansion in the huntingtin gene (HTT), and 44 healthy controls (HC). PBMC from the pre-HD and HD groups showed shorter telomeres (p < 0.0001) and a significant increase of pγ-H2AX compared to the controls (p < 0.0001). The levels of pγ-H2AX correlated robustly with the presence of the mutated gene in pre-HD and HD. The availability of a potentially reversible biomarker (pγ-H2AX) in the premanifest stage of HD, negligible in HC, provides a novel tool to monitor premanifest subjects and find patient-specific drugs. Ann Neurol 2018;00:1-6 ANN NEUROL 2019;85:296-301. [ABSTRACT FROM AUTHOR]

Background CpG dinucleotide-rich genomic DNA regions, known as CpG islands (CGIs), can be methylated at their cytosine residues as an epigenetic mark that is stably inherited during cell mitosis. Differentially methylated regions (DMRs) are genomic regions showing different degrees of DNA methylation in multiple samples. In this study, we focused our attention on CGIs showing different DNA methylation between two culture replicas of the same cell line. Results We used methylation data of 35 cell lines from the Encyclopedia of DNA Elements (ENCODE) consortium to identify CpG islands that were differentially methylated between replicas of the same cell line and denoted them Inter Replicas Differentially Methylated CpG islands (IRDM-CGIs). We identified a group of IRDM-CGIs that was consistently shared by different cell lines, and denoted it common IRDM-CGIs. X chromosome CGIs were overrepresented among common IRDM-CGIs. Autosomal IRDM-CGIs were preferentially located in gene bodies and intergenic regions had a lower G + C content, a smaller mean length, and a reduced CpG percentage. Functional analysis of the genes associated with autosomal IRDM-CGIs showed that many of them are involved in DNA binding and development. Conclusions Our results show that several specific functional and structural features characterize common IRDM-CGIs. They may represent a specific subset of CGIs that are more prone to being differentially methylated for their intrinsic characteristics. [ABSTRACT FROM AUTHOR]

OBJECTIVE -- We explore the relationship among BMI, habitual diet, and the Pro 12Ala polymorphism in the peroxisome proliferator--activated receptor (PPAR)γ2. RESEARCH DESIGN AND METHODS -- The Pro 12Ala variant was characterized in 343 unrelated type 2 diabetic patients who were consecutively seen at the outpatient clinic of a health district of the province of Naples. Anthropometric and laboratory parameters were measured; habitual diet was assessed by a validated semiquantitative food frequency questionnaire. RESULTS -- The overall frequency of Ala12 was 12% (n = 42). BMI was significantly higher in Ala carriers than non-Ala carriers, whereas total daily energy intake or macronutrient composition of the diet were similar in the two groups. For further analysis, participants were stratified according to genotype and sex-specific quartiles of energy intake. BMI increased in both genotype groups with increasing energy intake (P < 0.03). BMI was similar in Ala carriers and non-Ala carriers (30.0 vs. 30.1 kg/m², P > 0.10) in the lower quartile of energy intake but significantly higher in Ala carriers in the upper quartile (36.0 vs. 32.1 kg/m², P < 0.001). Average daily energy intake and diet composition were comparable within each quartile for carriers or noncarriers of the Ala allele. Relative to the noncarriers, Ala carriers had a significantly lower energy intake per kilogram body weight, thus suggesting that the Ala allele is associated with a higher food efficiency. The confounding role of medications, glucose control, and physical exercise was ruled out. CONCLUSIONS -- This study provides evidence of a differential susceptibility to fat accumulation, and, hence, weight gain, in response to habitual high energy intake for Ala carriers compared with. Pro/Pro homozygotes. [ABSTRACT FROM AUTHOR]

Enhanced oxidative stress and inflammation contribute to telomere erosion. Friedreich's ataxia is a neurodegenerative disorder caused by a reduction in frataxin expression that results in mitochondrial dysfunction and oxidative damage. Furthermore, frataxin deficiency induces a strong activation of inflammatory genes and neuronal death. We investigated telomere length (TL) in peripheral blood leukocytes of 37 patients with Friedreich's ataxia and 36 controls. We noted a significant telomere shortening in patients with Friedreich's ataxia compared to healthy controls (p=0.03). We also found a correlation between TL and disease duration (p=0.001). Our observations lead to the hypothesis that the TL of human peripheral blood leukocytes may serve as a biomarker of Friedreich's ataxia that could be used as an outcome measure in clinical trials.

Background: The primary aim of the present study was to determine the survival rates and identify predictors of disease duration in a cohort of Huntington's disease (HD) patients from Southern Italy., Methods: All medical records of HD patients followed between 1977 and 2008 at the Department of Neurological Sciences of Federico II University in Naples were retrospectively reviewed and 135 patients were enrolled in the analysis. At the time of data collection, 41 patients were deceased (19 males and 22 females) with a mean ± SD age at death of 56.6 ± 14.9 years (range 18-83)., Results: The median survival time was 20 years (95% CI: 18.3-21.7). Cox regression analysis showed that the number of CAG in the expanded allele (HR 1.09 for 1 point triplet increase, p=0.002) and age of onset (HR 1.05 for 1 point year increase, p=0.002) were independent and significant predictors of lower survival rates., Conclusions: We believe that these findings are important for a better understanding of the natural history of the disease and may be relevant in designing future therapeutic trials.

AKAP121 focuses distinct signaling events from membrane to mitochondria by binding and targeting cAMP-dependent protein kinase (PKA), protein tyrosine phosphatase (PTPD1), and mRNA. We find that AKAP121 also targets src tyrosine kinase to mitochondria via PTPD1. AKAP121 increased src-dependent phosphorylation of mitochondrial substrates and enhanced the activity of cytochrome c oxidase, a component of the mitochondrial respiratory chain. Mitochondrial membrane potential and ATP oxidative synthesis were enhanced by AKAP121 in an src- and PKA-dependent manner. Finally, siRNA-mediated silencing of endogenous AKAP121 drastically impaired synthesis and accumulation of mitochondrial ATP. These findings indicate that AKAP121, through its role in enhancing cAMP and tyrosine kinase signaling to distal organelles, is an important regulator in mitochondrial metabolism.

Degeneration of substantia nigra has been described in spinocerebellar ataxia type 2 (SCA2). In this study, dopamine transporter (DAT) density with [123 I]FP-CIT SPECT was studied in six SCA2 patients with no parkinsonian signs, six Parkinson's disease (PD) patients, and six controls. Marked striatal DAT loss was found in both SCA2 and PD patients. However, a more severe reduction in the caudate and a higher putamen to caudate ratio distinguished SCA2 from PD patients, suggesting a more uniform nigrostriatal impairment in SCA2. Striatal DAT density of SCA2 patients correlated with the severity of cerebellar ataxia.