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Aims: Astrocytic tau pathology is a major feature of tauopathies and ageing‐related tau astrogliopathy (ARTAG). The substantia nigra (SN) is one of the important degenerative areas in tauopathies with parkinsonism. Nigral tau pathology is usually reported as neuronal predominant with less prominent astrocytic involvement. We aimed to identify cases with prominent astrocytic tau pathology in the SN. Methods: We use the term nigral tau‐astrogliopathy (NITAG) to describe cases showing an unusually high density of ARTAG with less neuronal tau pathology in the SN. We collected clinical information and studied the distribution of tau pathology, morphological features and immunostaining profiles in three cases. Results: Three cases, all males with parkinsonism, were identified with the following clinicopathological diagnoses: (i) atypical parkinsonism with tau pathology reminiscent to that in postencephalitic parkinsonism (69‐year‐old); (ii) multiple system atrophy (73‐year‐old); (iii) traumatic encephalopathy syndrome/chronic traumatic encephalopathy (84‐year‐old). Double‐labelling immunofluorescence confirmed co‐localization of GFAP and phosphorylated tau in affected astrocytes. Staining profiles of NITAG revealed immunopositivity for various phosphorylated tau antibodies. Some astrocytic tau lesions were also seen in other brainstem regions and cerebral grey matter. Conclusions: We propose NITAG is a rare neuropathological feature, and not a distinct disease entity, in the frame of multiple system ARTAG, represented by abundant tau‐positive astrocytes in various brain regions but having the highest density in the SN. The concept of NITAG allows the stratification of cases with various background pathologies to understand its relevance and contribution to neuronal dysfunction. [ABSTRACT FROM AUTHOR]

Previous research has indicated that engaging in art activities is beneficial to both psychological and physical well-being; however, few studies have examined the link between attitudes toward art and well-being. In the present study, we have termed a positive and appreciative attitude toward art as savoring art and have investigated the relationship between savoring art and individual well-being. Study 1 (N = 501) examined the associations between savoring art and psychological well-being (PWB) as well as subjective well-being (SWB), the two most widely used terms for meaningful and hedonic happiness, respectively. The results suggested that savoring art was linked to a greater level of both PWB and SWB. Furthermore, Study 2 (N = 144) demonstrated that savoring art correlated with reduced biological health risk, as measured by objective biomarkers for inflammation and hypertension. The results from the present study highlight the potential psychological and physical benefits of savoring art, regardless of individuals' socioeconomic condition, level of openness to experience, or art engagement frequency. [ABSTRACT FROM AUTHOR]

The most frequent neurodegenerative proteinopathies include diseases with deposition of misfolded tau or α-synuclein in the brain. Pathological protein aggregates in the PNS are well-recognized in α-synucleinopathies and have recently attracted attention as a diagnostic biomarker. However, there is a paucity of observations in tauopathies. To characterize the involvement of the PNS in tauopathies, we investigated tau pathology in cranial and spinal nerves (PNS-tau) in 54 tauopathy cases [progressive supranuclear palsy (PSP), n = 15; Alzheimer's disease (AD), n = 18; chronic traumatic encephalopathy (CTE), n = 5; and corticobasal degeneration (CBD), n = 6; Pick's disease, n = 9; limbic-predominant neuronal inclusion body 4-repeat tauopathy (LNT), n = 1] using immunohistochemistry, Gallyas silver staining, biochemistry, and seeding assays. Most PSP cases revealed phosphorylated and 4-repeat tau immunoreactive tau deposits in the PNS as follows: (number of tau-positive cases/available cases) cranial nerves III: 7/8 (88%); IX/X: 10/11 (91%); and XII: 6/6 (100%); anterior spinal roots: 10/10 (100%). The tau-positive inclusions in PSP often showed structures with fibrillary (neurofibrillary tangle-like) morphology in the axon that were also recognized with Gallyas silver staining. CBD cases rarely showed fine granular non-argyrophilic tau deposits. In contrast, tau pathology in the PNS was not evident in AD, CTE and Pick's disease cases. The single LNT case also showed tau pathology in the PNS. In PSP, the severity of PNS-tau involvement correlated with that of the corresponding nuclei, although, occasionally, p-tau deposits were present in the cranial nerves but not in the related brainstem nuclei. Not surprisingly, most of the PSP cases presented with eye movement disorder and bulbar symptoms, and some cases also showed lower-motor neuron signs. Using tau biosensor cells, for the first time we demonstrated seeding capacity of tau in the PNS. In conclusion, prominent PNS-tau distinguishes PSP from other tauopathies. The morphological differences of PNS-tau between PSP and CBD suggest that the tau pathology in PNS could reflect that in the central nervous system. The high frequency and early presence of tau lesions in PSP suggest that PNS-tau may have clinical and biomarker relevance. [ABSTRACT FROM AUTHOR]

Lewy body diseases (LBDs) feature α-synuclein (α-syn)-containing Lewy bodies, with misfolded α-syn potentially propagating as seeds. Using a seeding amplification assay, we previously reported distinct α-syn seeding in LBD cases based on the area under seeding curves. This study revealed that LBD cases showing different α-syn seeding kinetics have distinct proteomics profiles, emphasizing disruptions in mitochondria and lipid metabolism in high-seeder cases. Though the mechanisms underlying LBD development are intricate, the factors influencing α-syn seeding activity remain elusive. To address this and complement our previous findings, we conducted targeted transcriptome analyses in the substantia nigra using the nanoString nCounter assay together with histopathological evaluations in high (n = 4) and low (n = 3) nigral α-syn seeders. Neuropathological findings (particularly the substantia nigra) were consistent between these groups and were characterized by neocortical LBD associated with Alzheimer's disease neuropathologic change. Among the 1811 genes assessed, we identified the top 20 upregulated and downregulated genes and pathways in α-syn high seeders compared with low seeders. Notably, alterations were observed in genes and pathways related to transmembrane transporters, lipid metabolism, and the ubiquitin–proteasome system in the high α-syn seeders. In conclusion, our findings suggest that the molecular behavior of α-syn is the driving force in the neurodegenerative process affecting the substantia nigra through these identified pathways. These insights highlight their potential as therapeutic targets for attenuating LBD progression. [ABSTRACT FROM AUTHOR]

This paper analyzes the state-dependent volatility transmission mechanism between oil, stock, dollar, and bond prices to further examine the role of oil price uncertainty in financial markets. To this end, we extend the Diebold and Yilmaz (2014) spillover framework by incorporating a Markov-switching model and a Bayesian MCMC algorithm. We find that oil prices spills the highest degree of volatility to other markets during crises. The interdependence between the stock and oil markets is solid and stable, regardless of the regime shift. In contrast, the effect of oil price uncertainty on the foreign exchange or bond market during crises is double that during non-crisis periods. This suggests that oil price is closely related to other asset classes and reinforces its role as a risk transmitter during a crisis. [ABSTRACT FROM AUTHOR]

Objective: Progressive supranuclear palsy (PSP) is a 4R‐tauopathy showing heterogeneous tau cytopathology commencing in the globus pallidus (GP) and the substantia nigra (SN), regions also associated with age‐related iron accumulation. Abnormal iron levels have been extensively associated with tau pathology in neurodegenerative brains, however, its role in PSP pathogenesis remains yet unknown. We perform the first cell type‐specific evaluation of PSP iron homeostasis and the closely related oxygen homeostasis, in relation to tau pathology in human postmortem PSP brains. Methods: In brain regions vulnerable to PSP pathology (GP, SN, and putamen), we visualized iron deposition in tau‐affected and unaffected neurons, astroglia, oligodendrocytes, and microglia, using a combination of iron staining with immunolabelling. To further explore molecular pathways underlying our observations, we examined the expression of key iron and oxygen homeostasis mRNA transcripts and proteins. Results: We found astrocytes as the major cell type accumulating iron in the early affected regions of PSP, highly associated with cellular tau pathology. The same regions are affected by dysregulated expression of alpha and beta hemoglobin and neuroglobin showing contrasting patterns. We discovered changes in iron and oxygen homeostasis‐related gene expression associated with aging of the brain, and identified dysregulated expression of rare neurodegeneration with brain iron accumulation (NBIA) genes associated with tau pathology to distinguish PSP from the healthy aging brain. Interpretation: We present novel aspects of PSP pathophysiology highlighting an overlap with NBIA pathways. Our findings reveal potential novel targets for therapy development and have implications beyond PSP for other iron‐associated neurodegenerative diseases. ANN NEUROL 2023;93:431–445 [ABSTRACT FROM AUTHOR]