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026, p = 0.87). In ASD, striatal dopamine synthesis capacity was not significantly associated with loneliness (β = 0.01, p = 0.96). Secondary analyses showed comparable results when examining the associative, limbic, and sensorimotor sub-regions of the striatum (all p-values > 0.05). Results were similar before and after adjusting for age, sex, smoking-status, and PET/CT-scanner-type. In conclusion, in unmedicated, non-psychotic adults with ASD, striatal dopamine synthesis capacity is not increased and not associated with social defeat.Iron deposition is present in main lesion areas in the brains of patients with Parkinson's disease (PD) and an abnormal iron content may be associated with dopaminergic neuronal cytotoxicity and degeneration in the substantia nigra of the midbrain. However, the cause of iron deposition and its role in the pathological process of PD are unclear. In the present study, we investigated the effects of the nasal mucosal delivery of synthetic human α-synuclein (α-syn) preformed fibrils (PFFs) on the pathogenesis of PD in Macaca fascicularis. We detected that iron deposition was clearly increased in a time-dependent manner from 1 to 17 months in the substantia nigra and globus pallidus, highly contrasting to other brain regions after treatments with α-syn PFFs. At the cellular level, the iron deposits were specifically localized in microglia but not in dopaminergic neurons, nor in other types of glial cells in the substantia nigra, whereas the expression of transferrin (TF), TF receptor 1 (TFR1), TF receptor 2 (TFR2), and ferroportin (FPn) was increased in dopaminergic neurons. Furthermore, no clear dopaminergic neuron loss was observed in the substantia nigra, but with decreased immunoreactivity of tyrosine hydroxylase (TH) and appearance of axonal swelling in the putamen. The brain region-enriched and cell-type-dependent iron localizations indicate that the intranasal α-syn PFFs treatment-induced iron depositions in microglia in the substantia nigra may appear as an early cellular response that may initiate neuroinflammation in the dopaminergic system before cell death occurs. Our data suggest that the inhibition of iron deposition may be a potential approach for the early prevention and treatment of PD.Phosphorylated H2A.X is a critical chromatin marker of DNA damage repair (DDR) in higher eukaryotes. However, H2A.X gene expression remains relatively uncharacterised. Replication-dependent (RD) histone genes generate poly(A)- mRNA encoding new histones to package DNA during replication. In contrast, replication-independent (RI) histone genes synthesise poly(A)+ mRNA throughout the cell cycle, translated into histone variants that confer specific epigenetic patterns on chromatin. Remarkably H2AFX, encoding H2A.X, is a hybrid histone gene, generating both poly(A)+ and poly(A)- mRNA isoforms. Here we report that the selective removal of either mRNA isoform reveals different effects in different cell types. In some cells, RD H2A.X poly(A)- mRNA generates sufficient histone for deposition onto DDR associated chromatin. In contrast, cells making predominantly poly(A)+ mRNA require this isoform for de novo H2A.X synthesis, required for efficient DDR. This highlights the importance of differential H2A.X mRNA 3'-end processing in the maintenance of effective DDR.Hypoxia-induced resistance of tumor cells to therapeutic treatment is an unresolved limitation due to poor vascular accessibility and protective cell adaptations provided by a network, including PERK, NRF2, and HIF signaling. All three pathways have been shown to influence each other, but a detailed picture remains elusive. To explore this crosstalk in the context of tumor therapy, we generated human cancer cell lines of pancreatic and lung origin carrying an inducible shRNA against NRF2 and PERK. We report that PERK-related phosphorylation of NRF2 is only critical in Keap1 wildtype cells to escape its degradation, but shows no direct effect on nuclear import or transcriptional activity of NRF2. We could further show that NRF2 is paramount for proliferation, ROS elimination, and radioprotection under constant hypoxia (1% O2), but is dispensable under normoxic conditions or after reoxygenation. Depletion of NRF2 does not affect apoptosis, cell cycle progression and proliferation factors AKT and c-Myc, but eliminates cellular HIF-1α signaling. Co-IP experiments revealed a protein interaction between NRF2 and HIF-1α and strongly suggest NRF2 as one of the cellular key factor for the HIF pathway. Together these data provide new insights on the complex role of the PERK-NRF2-HIF-axis for cancer growth.Aberrant neural oscillations hallmark numerous brain disorders. Here, we first report a method to track the phase of neural oscillations in real-time via endpoint-corrected Hilbert transform (ecHT) that mitigates the characteristic Gibbs distortion. We then used ecHT to show that the aberrant neural oscillation that hallmarks essential tremor (ET) syndrome, the most common adult movement disorder, can be transiently suppressed via transcranial electrical stimulation of the cerebellum phase-locked to the tremor. The tremor suppression is sustained shortly after the end of the stimulation and can be phenomenologically predicted. Finally, we use feature-based statistical-learning and neurophysiological-modelling to show that the suppression of ET is mechanistically attributed to a disruption of the temporal coherence of the aberrant oscillations in the olivocerebellar loop, thus establishing its causal role. The suppression of aberrant neural oscillation via phase-locked driven disruption of temporal coherence may in the future represent a powerful neuromodulatory strategy to treat brain disorders.Temporal dynamics and mechanisms underlying epigenetic changes in Huntington's disease (HD), a neurodegenerative disease primarily affecting the striatum, remain unclear. Using a slowly progressing knockin mouse model, we profile the HD striatal chromatin landscape at two early disease stages. Data integration with cell type-specific striatal enhancer and transcriptomic databases demonstrates acceleration of age-related epigenetic remodelling and transcriptional changes at neuronal- and glial-specific genes from prodromal stage, before the onset of motor deficits. see more We also find that 3D chromatin architecture, while generally preserved at neuronal enhancers, is altered at the disease locus. Specifically, we find that the HD mutation, a CAG expansion in the Htt gene, locally impairs the spatial chromatin organization and proximal gene regulation. Thus, our data provide evidence for two early and distinct mechanisms underlying chromatin structure changes in the HD striatum, correlating with transcriptional changes the HD mutation globally accelerates age-dependent epigenetic and transcriptional reprogramming of brain cell identities, and locally affects 3D chromatin organization.

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