Cerebellar ataxia results from various genetic and nongenetic disorders and is characterized by involuntary movements that impair precision and motor rhythm. Here, we report that climbing fiber (CF) denervation is a common pathophysiology underlying motor rhythm loss in cerebellar ataxia. By examining cerebellar pathology in patients with spinocerebellar ataxia (SCA) types 1, 2, and 6 and multiple system atrophy, we identified CF degeneration with synaptic loss as a shared pathophysiology. Optogenetic silencing of CF synaptic activity in mice induced ataxia-like motor dysfunctions and loss of motor precision. In addition, CF silencing resulted in cerebellar and motor rhythm loss, another core feature of ataxia. This rhythm loss was predominantly CF dependent and resistant to Purkinje cell-specific lesioning by diphtheria toxin. Correspondingly, two patients with inferior olive pathology, the brain site that provides CFs to Purkinje cells, presented with ataxia and cerebellar rhythm loss. Patients with genetic or nongenetic cerebellar ataxia exhibited cerebellar rhythm loss that correlated with the Scale for the Assessment and Rating of Ataxia. Chemogenetic stimulation of CFs improved cerebellar and motor rhythms as well as motor performance in the SCA type 1 mouse model of ataxia. These results suggest that CF-dependent cerebellar rhythm loss occurs across different types of cerebellar ataxia, contributing to motor imprecision and motor rhythm loss, two defining features of ataxia.
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http://dx.doi.org/10.1126/scitranslmed.adk3922 | DOI Listing |
Sleep Med
February 2025
Departamento de Neurocirurgia. Hospital A Beneficência de São Paulo, São Paulo, Brazil; Departamento de Neurologia e Neurocirurgia. Universidade Federal de São Paulo, São Paulo, Brazil. Electronic address:
Melatonin has been shown to improve sleep quality in Parkinson's disease (PD) patients with good safety and tolerability. Beyond its neurological benefits, emerging evidence suggests that melatonin may exert cardioprotective effects, which could be relevant in the context of sudden unexpected death in PD (SUDPAR). PD is associated with high mortality rates, and autonomic dysfunction and cardiac abnormalities may play a role in SUDPAR.
View Article and Find Full Text PDFThe rising incidence and death rates linked to Alzheimer's disease (AD) highlight an urgent issue. Genetic screening is celebrated as a significant advancement for its early detection capabilities, pinpointing those at risk before the emergence of symptoms. Yet, the limited availability of these technologies highlights a critical gap in widespread application.
View Article and Find Full Text PDFJ Virol Methods
March 2025
Department of Microbiology and Immunology, University of Texas Medical Branch, Galveston, TX 77555, United States; World Reference Center for Emerging Viruses and Arboviruses, Institute for Human Infections and Immunity, University of Texas Medical Branch, Galveston, TX 77555, United States. Electronic address:
Golden Syrian hamsters are an often-overlooked model in behavioral testing. While previously utilized for research examining circadian rhythms and mammalian reproduction, they are less common than murine models in both infectious disease and behavioral studies. However, coronavirus disease-19 (COVID-19) quickly pushed hamster modeling to the forefront due to its myriad of advantages over mice in recapitulating human pathology and transmission.
View Article and Find Full Text PDFObes Pillars
March 2025
Pennington Biomedical Research Center, Louisiana State University, 6400 Perkins Road, Baton Rouge, 70808, Louisiana, USA.
Background: Management of obesity potentially improves cardiometabolic risk factors in patients with metabolic syndrome (MetS). The Epitomee capsule is a non-pharmacological, biodegradable device treatment for weight reduction in patients with overweight and obesity.
Methods: This secondary analysis of the Randomized Evaluation of Safety and Efficacy of the Epitomee capsule Trial (RESET) (a randomized, 24-week, multicenter, placebo-controlled, double-blind trial that enrolled 279 adults aged ≥18 years with a BMI of 27-40 kg/m2) evaluated changes in cardiometabolic parameters in participants treated with Epitomee or placebo combined with lifestyle counseling among (a) the entire RESET study population, and (b) participants meeting diagnostic criteria for prediabetes.
bioRxiv
February 2025
Department of Pathology, Division of Molecular and Cellular Pathology, Heersink School of Medicine, University of Alabama at Birmingham, Birmingham, AL 35294, USA.
Alzheimer's disease (AD) is a progressive neurodegenerative disorder characterized by amyloid-β (Aβ) plaque accumulation, cognitive decline, lipid dysregulation, and neuroinflammation. Mutations in the Amyloid Precursor Protein (APP), and accumulation of A contribute to AD, however, underlying mechanisms linking beta amyloid to lipid metabolism and neuroinflammation remain unclear. Using models, we demonstrate that and lead to progressive locomotor impairments, disrupted sleep activity, memory deficits, lipid dysregulation, loss of synaptic integrity, and neuroinflammation.
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