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Summary Huntington's disease (HD) is an autosomal dominant disorder with progressive motor dysfunction and cognitive decline. The disease is caused by a CAG repeat expansion in the IT15 gene, which elongates a polyglutamine stretch of the HD protein, Huntingtin. No therapeutic treatments are available, and new pharmacological targets are needed. Retrotransposons are transposable elements (TEs) that represent 40% and 30% of the human and Drosophila genomes and replicate through an RNA intermediate. Mounting evidence suggests that mammalian TEs are active during neurogenesis and may be involved in diseases of the nervous system. Here we show that TE expression and mobilization are increased in a Drosophila melanogaster HD model. By inhibiting TE mobilization with Reverse Transcriptase inhibitors, polyQ-dependent eye neurodegeneration and genome instability in larval brains are rescued and fly lifespan is increased. These results suggest that TE activation may be involved in polyQ-induced neurotoxicity and a potential pharmacological target., Graphical abstract, Highlights • Transposable elements: new pathogenic players in Huntington's disease • polyQ-Htt expression leads to widespread heterochromatin relaxation • Reverse transcriptase inhibitors rescue HD-induced neurodegeneration, Biological sciences; Molecular biology; Neuroscience

Summary: Chromatin organization plays a crucial role in tissue homeostasis. Heterochromatin relaxation and consequent unscheduled mobilization of transposable elements (TEs) are emerging as key contributors of aging and aging-related pathologies, including Alzheimer’s disease (AD) and cancer. However, the mechanisms governing heterochromatin maintenance or its relaxation in pathological conditions remain poorly understood. Here we show that PIN1, the only phosphorylation-specific cis/trans prolyl isomerase, whose loss is associated with premature aging and AD, is essential to preserve heterochromatin. We demonstrate that this PIN1 function is conserved from Drosophila to humans and prevents TE mobilization-dependent neurodegeneration and cognitive defects. Mechanistically, PIN1 maintains nuclear type-B Lamin structure and anchoring function for heterochromatin protein 1α (HP1α). This mechanism prevents nuclear envelope alterations and heterochromatin relaxation under mechanical stress, which is a key contributor to aging-related pathologies.

BackgroundTransposable elements (TEs) widely contributed to the evolution of genomes allowing genomic innovations, generating germinal and somatic heterogeneity and giving birth to long non-coding RNAs (lncRNAs). These features have been associated to the evolution, functioning and complexity of the nervous system at such a level that somatic retrotransposition of long interspersed element (LINE) L1 has been proposed to be associated to human cognition. Among invertebrates, octopuses are fascinating animals whose nervous system reaches a high level of complexity achieving sophisticated cognitive abilities. The sequencing of the genome of theOctopus bimaculoidesrevealed a striking expansion of TEs which were proposed to have contributed to the evolution of its complex nervous system. We recently found a similar expansion also in the genome ofOctopus vulgaris. However a specific search for the existence of full-length transpositionally competent TEs has not been performed in this genus.ResultsHere we report the identification of LINE elements competent for retrotransposition inOctopus vulgarisandOctopus bimaculoidesand show evidence suggesting that they might be active driving germline polymorphisms among individuals and somatic polymorphisms in the brain. Transcription and translation measured for one of these elements resulted in specific signals in neurons belonging to areas associated with behavioral plasticity. We also report the transcription of thousands of lncRNAs and the pervasive inclusion of TE fragments in the transcriptomes of bothOctopusspecies, further testifying the crucial activity of TEs in the evolution of the octopus genomes.ConclusionsThe neural transcriptome of the octopus shows the transcription of thousands of putative lncRNAs and of a full lenght LINE element belonging to the RTE class. We speculate that a convergent evolutionary process involving retrotransposons activity in the brain has been important for the evolution of sophisticated cognitive abilities in this genus.

Minisatellites, also called variable number of tandem repeats (VNTRs), are a class of repetitive elements that may affect gene expression at multiple levels and have been correlated to disease. Their identification and role as expression quantitative trait loci (eQTL) have been limited by their absence in comparative genomic hybridization and single nucleotide polymorphisms arrays. By taking advantage of cap analysis of gene expression (CAGE), we describe a new example of a minisatellite hosting a transcription start site (TSS) which expression is dependent on the repeat number. It is located in the third intron of the gene nitrogen permease regulator like protein 3 (NPRL3). NPRL3 is a component of the GAP activity toward rags 1 protein complex that inhibits mammalian target of rapamycin complex 1 (mTORC1) activity and it is found mutated in familial focal cortical dysplasia and familial focal epilepsy. CAGE tags represent an alternative TSS identifying TAGNPRL3 messenger RNAs (mRNAs). TAGNPRL3 is expressed in red blood cells both at mRNA and protein levels, it interacts with its protein partner NPRL2 and its overexpression inhibits cell proliferation. This study provides an example of a minisatellite that is both a TSS and an eQTL as well as identifies a new VNTR that may modify mTORC1 activity.

Artemisinin derivatives such as dihydroartemisinin (DHA) induce significant depletion of early embryonic erythroblasts in animal models. We have reported previously that DHA specifically targets pro-erythroblasts and basophilic erythroblasts, when human CD34+ stem cells are differentiated toward the erythroid lineage, indicating that a window of susceptibility to artemisinins may exist also in human developmental erythropoiesis during pregnancy. To better investigate the toxicity of artemisinin derivatives, the structure-activity relationship was evaluated against the K562 leukaemia cell line, used as a model for differentiating early human erythroblasts. All artemisinins derivatives, except deoxyartemisinin, inhibited both spontaneous and induced erythroid differentiation, confirming that the peroxide bridge is responsible for the erythro-toxicity. On the contrary, cell growth was markedly reduced by DHA, artemisone and artesunate but not by artemisinin, 10-deoxoartemisinin or deoxy-artemisinin. The substituent at position C-10 is responsible only for the anti-proliferative effect, since 10-deoxoartemisinin did not reduce cell growth but arrested the differentiation of K562 cells. In particular, the results showed that DHA resulted the most potent and rapidly acting compound of the drug family, causing (i) the decreased expression of GpA surface receptors and the down regulation the γ-globin gene; (ii) the alteration of S phase of cell cycle and (iii) the induction of programmed cell death of early erythroblasts in a dose dependent manner within 24h. In conclusion, these findings confirm that the active metabolite DHA is responsible for the erythro-toxicity of most of artemisinins used in therapy. Thus, as long as no further clinical data are available, current WHO recommendations of avoiding malaria treatment with artemisinins during the first trimester of pregnancy remain valid.

Diagnosis of malaria must be rapid, accurate, simple to use, portable and low cost, as suggested by the World Health Organization (WHO). Despite recent efforts, the gold standard remains the light microscopy of a stained blood film. This method can detect low parasitemia and identify different species of Plasmodium. However, it is time consuming, it requires well trained microscopist and good instrumentation to minimize misinterpretation, thus the costs are considerable. Moreover, the equipment cannot be easily transported and installed. In this paper we propose a new technique named "secondary speckle sensing microscopy" ((SM)-M-3) based upon extraction of correlation based statistics of speckle patterns generated while illuminating red blood cells with a laser and inspecting them under a microscope. Then, using fuzzy logic ruling and principle component analysis, good quality of separation between healthy and infected red blood cells was demonstrated in preliminary experiments. The proposed technique can be used for automated high rate detection of malaria infected red blood cells. (c) 2012 Optical Society of America

Evidence, obtained in rodent and primate models of Parkinsons disease (PD) and in preliminary clinical trials, indicates that adenosine A receptor antagonists might represent a promising non-dopaminergic therapeutic tool for the treatment of PD. Recently, we have reported the biological evaluation of 8-substituted 9-ethyladenines (ANR) as new A receptor antagonists, three of which (ANR 82, ANR 94, and ANR 152) showed high efficacy in in vivo models for Parkinsons. Understanding the metabolic pathways of new drug candidates is an important aspect of drug discovery. The ANR compounds have been investigated in order to clarify their activity on rat liver microsomes, and more specifically on recombinant human cytochrome P450 2D6 (CYP2D6). The metabolites of all three compounds were detected by liquid chromatography/tandem mass spectrometry (LC-MS/MS). The results indicate that this class of 9-ethyladenines is metabolized only to a fraction of 1.5-5%. These compounds also act as potent mechanism-based inhibitors of CYP450 and in particular of human isoform CYP2D6. Kinetic-analysis of enzyme inactivation was used to describe the effect of these time-dependent inhibitors and to derive the inhibition parameters K and K defined with respect to the O-demethylation of dextromethorphan.

Background Parkinson’s disease (PD) is a chronic progressive neurodegenerative disorder that is clinically defined in terms of motor symptoms. These are preceded by prodromal non-motor manifestations that prove the systemic nature of the disease. Identifying genes and pathways altered in living patients provide new information on the diagnosis and pathogenesis of sporadic PD. Methods Changes in gene expression in the blood of 40 sporadic PD patients and 20 healthy controls ("Discovery set") were analyzed by taking advantage of the Affymetrix platform. Patients were at the onset of motor symptoms and before initiating any pharmacological treatment. Data analysis was performed by applying Ranking-Principal Component Analysis, PUMA and Significance Analysis of Microarrays. Functional annotations were assigned using GO, DAVID, GSEA to unveil significant enriched biological processes in the differentially expressed genes. The expressions of selected genes were validated using RT-qPCR and samples from an independent cohort of 12 patients and controls ("Validation set"). Results Gene expression profiling of blood samples discriminates PD patients from healthy controls and identifies differentially expressed genes in blood. The majority of these are also present in dopaminergic neurons of the Substantia Nigra, the key site of neurodegeneration. Together with neuronal apoptosis, lymphocyte activation and mitochondrial dysfunction, already found in previous analysis of PD blood and post-mortem brains, we unveiled transcriptome changes enriched in biological terms related to epigenetic modifications including chromatin remodeling and methylation. Candidate transcripts as CBX5, TCF3, MAN1C1 and DOCK10 were validated by RT-qPCR. Conclusions Our data support the use of blood transcriptomics to study neurodegenerative diseases. It identifies changes in crucial components of chromatin remodeling and methylation machineries as early events in sporadic PD suggesting epigenetics as target for therapeutic intervention. Electronic supplementary material The online version of this article (doi:10.1186/s12864-015-2058-3) contains supplementary material, which is available to authorized users.

In this paper we present a novel image processing algorithm providing good preliminary capabilities for in vitro detection of malaria. The proposed concept is based upon analysis of the temporal variation of each pixel. Changes in dark pixels mean that inter cellular activity happened, indicating the presence of the malaria parasite inside the cell. Preliminary experimental results involving analysis of red blood cells being either healthy or infected with malaria parasites, validated the potential benefit of the proposed numerical approach. S.F. acknowledges the grant from Area Science Park of Trieste. J.G. acknowledges the support he got from project FIS2013-47548-P. D.M. and B.F. acknowledge the support from Project BIA2011-22704.

We propose a new technique for malaria detection. It is based upon extraction of correlation based statistics of speckle patterns generated while illuminating red blood cells with a laser and inspecting them under a microscope.

Evidence, obtained in rodent and primate models of Parkinson's disease (PD) and in preliminary clinical trials, indicates that adenosine A(2A) receptor antagonists might represent a promising non-dopaminergic therapeutic tool for the treatment of PD. Recently, we have reported the biological evaluation of 8-substituted 9-ethyladenines (ANR) as new A(2A) receptor antagonists, three of which (ANR 82, ANR 94, and ANR 152) showed high efficacy in in vivo models for Parkinson's. Understanding the metabolic pathways of new drug candidates is an important aspect of drug discovery. The ANR compounds have been investigated in order to clarify their activity on rat liver microsomes, and more specifically on recombinant human cytochrome P450 2D6 (CYP2D6). The metabolites of all three compounds were detected by liquid chromatography/tandem mass spectrometry (LC-MS/MS). The results indicate that this class of 9-ethyladenines is metabolized only to a fraction of 1.5-5%. These compounds also act as potent mechanism-based inhibitors of CYP450 and in particular of human isoform CYP2D6. Kinetic-analysis of enzyme inactivation was used to describe the effect of these time-dependent inhibitors and to derive the inhibition parameters K(inact) and K(i) defined with respect to the O-demethylation of dextromethorphan.

The multivariate algorithm hierarchical cluster analysis is applied to sets of resonance Raman spectra collected from human erythrocytes infected with the malaria parasite Plasmodium falciparum. The images obtained yield information about the distribution of hemoglobin and hemozoin (or malaria pigment) within the parasitized cells and about their molecular structure. This method has the advantage of conveying more information than other imaging approaches based on resonance Raman spectroscopy, and it is a promising tool to study the hemozoin formation process and its interaction with antimalarial drugs within unstained, well-preserved parasites.