183 results on '"Roy V. Sillitoe"'
Search Results
2. The cerebellum contributes to generalized seizures by altering activity in the ventral posteromedial nucleus
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Jaclyn Beckinghausen, Joshua Ortiz-Guzman, Tao Lin, Benjamin Bachman, Luis E. Salazar Leon, Yu Liu, Detlef H. Heck, Benjamin R. Arenkiel, and Roy V. Sillitoe
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Biology (General) ,QH301-705.5 - Abstract
Abstract Thalamo-cortical networks are central to seizures, yet it is unclear how these circuits initiate seizures. We test whether a facial region of the thalamus, the ventral posteromedial nucleus (VPM), is a source of generalized, convulsive motor seizures and if convergent VPM input drives the behavior. To address this question, we devise an in vivo optogenetic mouse model to elicit convulsive motor seizures by driving these inputs and perform single-unit recordings during awake, convulsive seizures to define the local activity of thalamic neurons before, during, and after seizure onset. We find dynamic activity with biphasic properties, raising the possibility that heterogenous activity promotes seizures. Virus tracing identifies cerebellar and cerebral cortical afferents as robust contributors to the seizures. Of these inputs, only microinfusion of lidocaine into the cerebellar nuclei blocks seizure initiation. Our data reveal the VPM as a source of generalized convulsive seizures, with cerebellar input providing critical signals.
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- 2023
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3. Glutamatergic cerebellar neurons differentially contribute to the acquisition of motor and social behaviors
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Meike E. van der Heijden, Alejandro G. Rey Hipolito, Linda H. Kim, Dominic J. Kizek, Ross M. Perez, Tao Lin, and Roy V. Sillitoe
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Science - Abstract
Abstract Insults to the developing cerebellum can cause motor, language, and social deficits. Here, we investigate whether developmental insults to different cerebellar neurons constrain the ability to acquire cerebellar-dependent behaviors. We perturb cerebellar cortical or nuclei neuron function by eliminating glutamatergic neurotransmission during development, and then we measure motor and social behaviors in early postnatal and adult mice. Altering cortical and nuclei neurons impacts postnatal motor control and social vocalizations. Normalizing neurotransmission in cortical neurons but not nuclei neurons restores social behaviors while the motor deficits remain impaired in adults. In contrast, manipulating only a subset of nuclei neurons leaves social behaviors intact but leads to early motor deficits that are restored by adulthood. Our data uncover that glutamatergic neurotransmission from cerebellar cortical and nuclei neurons differentially control the acquisition of motor and social behaviors, and that the brain can compensate for some but not all perturbations to the developing cerebellum.
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- 2023
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4. Function and dysfunction of the dystonia network: an exploration of neural circuits that underlie the acquired and isolated dystonias
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Jason S. Gill, Megan X. Nguyen, Mariam Hull, Meike E. van der Heijden, Ken Nguyen, Sruthi P. Thomas, and Roy V. Sillitoe
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dystonia ,cerebellum ,dyskinetic cerebral palsy ,dystonia network ,network disorder ,Neurology. Diseases of the nervous system ,RC346-429 ,Diseases of the musculoskeletal system ,RC925-935 - Abstract
Dystonia is a highly prevalent movement disorder that can manifest at any time across the lifespan. An increasing number of investigations have tied this disorder to dysfunction of a broad “dystonia network” encompassing the cerebellum, thalamus, basal ganglia, and cortex. However, pinpointing how dysfunction of the various anatomic components of the network produces the wide variety of dystonia presentations across etiologies remains a difficult problem. In this review, a discussion of functional network findings in non-mendelian etiologies of dystonia is undertaken. Initially acquired etiologies of dystonia and how lesion location leads to alterations in network function are explored, first through an examination of cerebral palsy, in which early brain injury may lead to dystonic/dyskinetic forms of the movement disorder. The discussion of acquired etiologies then continues with an evaluation of the literature covering dystonia resulting from focal lesions followed by the isolated focal dystonias, both idiopathic and task dependent. Next, how the dystonia network responds to therapeutic interventions, from the “geste antagoniste” or “sensory trick” to botulinum toxin and deep brain stimulation, is covered with an eye towards finding similarities in network responses with effective treatment. Finally, an examination of how focal network disruptions in mouse models has informed our understanding of the circuits involved in dystonia is provided. Together, this article aims to offer a synthesis of the literature examining dystonia from the perspective of brain networks and it provides grounding for the perspective of dystonia as disorder of network function.
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- 2023
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5. Cerebellar dysfunction in rodent models with dystonia, tremor, and ataxia
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Meike E. van der Heijden and Roy V. Sillitoe
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dystonia ,tremor ,cerebellum ,rodent ,ataxia ,Neurology. Diseases of the nervous system ,RC346-429 ,Diseases of the musculoskeletal system ,RC925-935 - Abstract
Dystonia is a movement disorder characterized by involuntary co- or over-contractions of the muscles, which results in abnormal postures and movements. These symptoms arise from the pathophysiology of a brain-wide dystonia network. There is mounting evidence suggesting that the cerebellum is a central node in this network. For example, manipulations that target the cerebellum cause dystonic symptoms in mice, and cerebellar neuromodulation reduces these symptoms. Although numerous findings provide insight into dystonia pathophysiology, they also raise further questions. Namely, how does cerebellar pathophysiology cause the diverse motor abnormalities in dystonia, tremor, and ataxia? Here, we describe recent work in rodents showing that distinct cerebellar circuit abnormalities could define different disorders and we discuss potential mechanisms that determine the behavioral presentation of cerebellar diseases.
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- 2023
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6. Author Correction: The cerebellum contributes to generalized seizures by altering activity in the ventral posteromedial nucleus
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Jaclyn Beckinghausen, Joshua Ortiz-Guzman, Tao Lin, Benjamin Bachman, Luis E. Salazar Leon, Yu Liu, Detlef H. Heck, Benjamin R. Arenkiel, and Roy V. Sillitoe
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Biology (General) ,QH301-705.5 - Published
- 2024
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7. Editorial: Models, mechanisms, and maturation in developmental dystonia
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Jason S. Gill, Meike E. van der Heijden, Aasef G. Shaikh, and Roy V. Sillitoe
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dystonia ,development ,maturation ,models ,mechanism ,Neurology. Diseases of the nervous system ,RC346-429 ,Diseases of the musculoskeletal system ,RC925-935 - Published
- 2023
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8. Disrupted sleep in dystonia depends on cerebellar function but not motor symptoms in mice
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Luis E. Salazar Leon and Roy V. Sillitoe
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dystonia ,sleep ,circadian rhythms ,Purkinje cells ,cerebellar nuclei ,Neurology. Diseases of the nervous system ,RC346-429 ,Diseases of the musculoskeletal system ,RC925-935 - Abstract
Although dystonia is the third most common movement disorder, patients often also experience debilitating nonmotor defects including impaired sleep. The cerebellum is a central component of a “dystonia network” that plays various roles in sleep regulation. Importantly, the primary driver of sleep impairments in dystonia remains poorly understood. The cerebellum, along with other nodes in the motor circuit, could disrupt sleep. However, it is unclear how the cerebellum might alter sleep and mobility. To disentangle the impact of cerebellar dysfunction on motion and sleep, we generated two mouse genetic models of dystonia that have overlapping cerebellar circuit miswiring but show differing motor phenotype severity: Ptf1aCre;Vglut2fx/fx and Pdx1Cre;Vglut2fx/fx mice. In both models, excitatory climbing fiber to Purkinje cell neurotransmission is blocked, but only the Ptf1aCre;Vglut2fx/fx mice have severe twisting. Using in vivo ECoG and EMG recordings we found that both mutants spend greater time awake and in NREM sleep at the expense of REM sleep. The increase in awake time is driven by longer awake bouts rather than an increase in bout number. We also found a longer latency to reach REM in both mutants, which is similar to what is reported in human dystonia. We uncovered independent but parallel roles for cerebellar circuit dysfunction and motor defects in promoting sleep quality versus posture impairments in dystonia.
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- 2023
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9. Proceedings of the 10th annual deep brain stimulation think tank: Advances in cutting edge technologies, artificial intelligence, neuromodulation, neuroethics, interventional psychiatry, and women in neuromodulation
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Joshua K. Wong, Helen S. Mayberg, Doris D. Wang, R. Mark Richardson, Casey H. Halpern, Lothar Krinke, Mattia Arlotti, Lorenzo Rossi, Alberto Priori, Sara Marceglia, Ro’ee Gilron, James F. Cavanagh, Jack W. Judy, Svjetlana Miocinovic, Annaelle D. Devergnas, Roy V. Sillitoe, Stephanie Cernera, Carina R. Oehrn, Aysegul Gunduz, Wayne K. Goodman, Erika A. Petersen, Helen Bronte-Stewart, Robert S. Raike, Mahsa Malekmohammadi, David Greene, Petra Heiden, Huiling Tan, Jens Volkmann, Valerie Voon, Luming Li, Pankaj Sah, Terry Coyne, Peter A. Silburn, Cynthia S. Kubu, Anna Wexler, Jennifer Chandler, Nicole R. Provenza, Sarah R. Heilbronner, Marta San Luciano, Christopher J. Rozell, Michael D. Fox, Coralie de Hemptinne, Jaimie M. Henderson, Sameer A. Sheth, and Michael S. Okun
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deep brain stimulation (DBS) ,artificial intelligence ,neuroethics ,Parkinson’s disease ,dystonia ,interventional psychiatry ,Neurosciences. Biological psychiatry. Neuropsychiatry ,RC321-571 - Abstract
The deep brain stimulation (DBS) Think Tank X was held on August 17–19, 2022 in Orlando FL. The session organizers and moderators were all women with the theme women in neuromodulation. Dr. Helen Mayberg from Mt. Sinai, NY was the keynote speaker. She discussed milestones and her experiences in developing depression DBS. The DBS Think Tank was founded in 2012 and provides an open platform where clinicians, engineers and researchers (from industry and academia) can freely discuss current and emerging DBS technologies as well as the logistical and ethical issues facing the field. The consensus among the DBS Think Tank X speakers was that DBS has continued to expand in scope however several indications have reached the “trough of disillusionment.” DBS for depression was considered as “re-emerging” and approaching a slope of enlightenment. DBS for depression will soon re-enter clinical trials. The group estimated that globally more than 244,000 DBS devices have been implanted for neurological and neuropsychiatric disorders. This year’s meeting was focused on advances in the following areas: neuromodulation in Europe, Asia, and Australia; cutting-edge technologies, closed loop DBS, DBS tele-health, neuroethics, lesion therapy, interventional psychiatry, and adaptive DBS.
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- 2023
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10. Influence of data sampling methods on the representation of neural spiking activity in vivo
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Meike E. van der Heijden, Amanda M. Brown, and Roy V. Sillitoe
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Biological sciences ,Biological sciences research methodologies ,Methodology in biological sciences ,Neuroscience ,Science - Abstract
Summary: In vivo single-unit recordings distinguish the basal spiking properties of neurons in different experimental settings and disease states. Here, we examined over 300 spike trains recorded from Purkinje cells and cerebellar nuclei neurons to test whether data sampling approaches influence the extraction of rich descriptors of firing properties. Our analyses included neurons recorded in awake and anesthetized control mice, and disease models of ataxia, dystonia, and tremor. We find that recording duration circumscribes overall representations of firing rate and pattern. Notably, shorter recording durations skew estimates for global firing rate variability toward lower values. We also find that only some populations of neurons in the same mouse are more similar to each other than to neurons recorded in different mice. These data reveal that recording duration and approach are primary considerations when interpreting task-independent single neuron firing properties. If not accounted for, group differences may be concealed or exaggerated.
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- 2022
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11. Kctd7 deficiency induces myoclonic seizures associated with Purkinje cell death and microvascular defects
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Justine H. Liang, Jonathan Alevy, Viktor Akhanov, Ryan Seo, Cory A. Massey, Danye Jiang, Joy Zhou, Roy V. Sillitoe, Jeffrey L. Noebels, and Melanie A. Samuel
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kctd7 ,epilepsy ,seizure ,motor defects ,cerebellum ,vasculature ,Medicine ,Pathology ,RB1-214 - Published
- 2022
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12. Neuromodulation of the cerebellum rescues movement in a mouse model of ataxia
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Lauren N. Miterko, Tao Lin, Joy Zhou, Meike E. van der Heijden, Jaclyn Beckinghausen, Joshua J. White, and Roy V. Sillitoe
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Science - Abstract
Deep brain stimulation (DBS) has potential for several movement disorders. Here the authors show that DBS improves motor function in a mouse model of ataxia.
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- 2021
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13. Wearable Peripheral Electrical Stimulation Devices for the Reduction of Essential Tremor: A Review
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Alexandra Karamesinis, Roy V. Sillitoe, and Abbas Z. Kouzani
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Essential tremor ,treatment ,wearable device ,sensor ,electrical stimulation ,algorithm ,Electrical engineering. Electronics. Nuclear engineering ,TK1-9971 - Abstract
Essential tremor is the most common pathological tremor, with a prevalence of 6.3% in people over 65 years of age. This disorder interferes with a patient’s ability to carry out activities of daily living independently, and treatment with medical and surgical interventions is often insufficient or contraindicated. Mechanical orthoses have not been widely adopted by patients due to discomfort and lack of discretion. Over the past 30 years, peripheral electrical stimulation has been investigated as a possible treatment for patients who have not found other treatment options to be satisfactory, with wearable devices revolutionizing this emerging approach in recent years. In this paper, an overview of essential tremor and its current medical and surgical treatment options are presented. Following this, tremor detection, measurement and characterization methods are explored with a focus on the measurement options that can be incorporated into wearable devices. Then, novel interventions for essential tremor are described, with a detailed review of open and closed-loop peripheral electrical stimulation methods. Finally, discussion of the need for wearable closed-loop peripheral electrical stimulation devices for essential tremor, approaches in their implementation, and gaps in the literature for further research are presented.
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- 2021
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14. Cerebellar Coordination of Neuronal Communication in Cerebral Cortex
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Samuel S. McAfee, Yu Liu, Roy V. Sillitoe, and Detlef H. Heck
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cerebellum ,cerebrocerebellar communication ,coherence ,functional connectivity ,cognition ,Neurosciences. Biological psychiatry. Neuropsychiatry ,RC321-571 - Abstract
Cognitive processes involve precisely coordinated neuronal communications between multiple cerebral cortical structures in a task specific manner. Rich new evidence now implicates the cerebellum in cognitive functions. There is general agreement that cerebellar cognitive function involves interactions between the cerebellum and cerebral cortical association areas. Traditional views assume reciprocal interactions between one cerebellar and one cerebral cortical site, via closed-loop connections. We offer evidence supporting a new perspective that assigns the cerebellum the role of a coordinator of communication. We propose that the cerebellum participates in cognitive function by modulating the coherence of neuronal oscillations to optimize communications between multiple cortical structures in a task specific manner.
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- 2022
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15. Multi-Disease Deep Brain Stimulation
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Mahboubeh Parastarfeizabadi, Roy V. Sillitoe, and Abbas Z. Kouzani
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Biomarkers ,closed-loop ,deep brain stimulation ,fuzzy logic ,multiple diseases ,Electrical engineering. Electronics. Nuclear engineering ,TK1-9971 - Abstract
Current closed-loop deep brain stimulation (DBS) devices can generally tackle one disorder. This paper presents the design and evaluation of a multi-disease closed-loop DBS device that can sense multiple brain biomarkers, detect a disorder, and adaptively deliver electrical stimulation pulses based on the disease state. The device consists of: (i) a neural sensor, (ii) a controller involving a feature extractor, a disease classifier, and a control strategy, and (iii) neural stimulator. The neural sensor records and processes local field potentials and spikes from within the brain using two low-frequency and high-frequency channels. The feature extractor digitally processes the output of the neural sensor, and extracts five potential biomarkers: alpha, beta, slow gamma, high-frequency oscillations, and spikes. The disease classifier identifies the type of the neurological disorder through an analysis of the biomarkers' amplitude features. The control strategy considers the disease state and supplies the stimulation settings to the neural stimulator. Both the disease classifier and control strategy are based on fuzzy algorithms. The neural stimulator generates electrical stimulation pulses according to the control commands, and delivers them to the target area of the brain. The device can generate current stimulation pulses with specific amplitude, frequency, and duration. The fabricated device has the maximum radius of 15 mm. Its total weight including the circuit board, battery and battery holder is 5.1 g. The performance of the integrated device has been evaluated through six bench and in-vitro experiments. The experimental results are presented, analyzed, and discussed. Six bench and in-vitro experiments were conducted using sinusoidal, normal pre-recorded, and diseased neural signals representing normal, epilepsy, depression and PD conditions. The results obtained through these tests indicate the successful neural sensing, classification, control, and neural stimulating performance.
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- 2020
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16. Propranolol Modulates Cerebellar Circuit Activity and Reduces Tremor
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Joy Zhou, Meike E. Van der Heijden, Luis E. Salazar Leon, Tao Lin, Lauren N. Miterko, Dominic J. Kizek, Ross M. Perez, Matea Pavešković, Amanda M. Brown, and Roy V. Sillitoe
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cerebellum ,tremor ,propranolol ,circuitry ,beta-adrenergic receptors ,electrophysiology ,Cytology ,QH573-671 - Abstract
Tremor is the most common movement disorder. Several drugs reduce tremor severity, but no cures are available. Propranolol, a β-adrenergic receptor blocker, is the leading treatment for tremor. However, the in vivo circuit mechanisms by which propranolol decreases tremor remain unclear. Here, we test whether propranolol modulates activity in the cerebellum, a key node in the tremor network. We investigated the effects of propranolol in healthy control mice and Car8wdl/wdl mice, which exhibit pathophysiological tremor and ataxia due to cerebellar dysfunction. Propranolol reduced physiological tremor in control mice and reduced pathophysiological tremor in Car8wdl/wdl mice to control levels. Open field and footprinting assays showed that propranolol did not correct ataxia in Car8wdl/wdl mice. In vivo recordings in awake mice revealed that propranolol modulates the spiking activity of control and Car8wdl/wdl Purkinje cells. Recordings in cerebellar nuclei neurons, the targets of Purkinje cells, also revealed altered activity in propranolol-treated control and Car8wdl/wdl mice. Next, we tested whether propranolol reduces tremor through β1 and β2 adrenergic receptors. Propranolol did not change tremor amplitude or cerebellar nuclei activity in β1 and β2 null mice or Car8wdl/wdl mice lacking β1 and β2 receptor function. These data show that propranolol can modulate cerebellar circuit activity through β-adrenergic receptors and may contribute to tremor therapeutics.
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- 2022
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17. Mood Regulatory Actions of Active and Sham Nucleus Accumbens Deep Brain Stimulation in Antidepressant Resistant Rats
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Rajas P. Kale, Thanh Thanh L. Nguyen, J. Blair Price, Nathanael J. Yates, Ken Walder, Michael Berk, Roy V. Sillitoe, Abbas Z. Kouzani, and Susannah J. Tye
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deep brain stimualtion ,nucleus accumbens ,GSK3—glycogen synthase kinase 3 ,rodent ,mTOR—mammalian target of rapamycin ,mood ,Neurosciences. Biological psychiatry. Neuropsychiatry ,RC321-571 - Abstract
The antidepressant actions of deep brain stimulation (DBS) are associated with progressive neuroadaptations within the mood network, modulated in part, by neurotrophic mechanisms. We investigated the antidepressant-like effects of chronic nucleus accumbens (NAc) DBS and its association with change in glycogen synthase kinase 3 (GSK3) and mammalian target of rapamycin (mTOR) expression in the infralimbic cortex (IL), and the dorsal (dHIP) and ventral (vHIP) subregions of the hippocampus of antidepressant resistant rats. Antidepressant resistance was induced via daily injection of adrenocorticotropic hormone (ACTH; 100 μg/day; 15 days) and confirmed by non-response to tricyclic antidepressant treatment (imipramine, 10 mg/kg). Portable microdevices provided continuous bilateral NAc DBS (130 Hz, 200 μA, 90 μs) for 7 days. A control sham electrode group was included, together with ACTH- and saline-treated control groups. Home cage monitoring, open field, sucrose preference, and, forced swim behavioral tests were performed. Post-mortem levels of GSK3 and mTOR, total and phosphorylated, were determined with Western blot. As previously reported, ACTH treatment blocked the immobility-reducing effects of imipramine in the forced swim test. In contrast, treatment with either active DBS or sham electrode placement in the NAc significantly reduced forced swim immobility time in ACTH-treated animals. This was associated with increased homecage activity in the DBS and sham groups relative to ACTH and saline groups, however, no differences in locomotor activity were observed in the open field test, nor were any group differences seen for sucrose consumption across groups. The antidepressant-like actions of NAc DBS and sham electrode placements were associated with an increase in levels of IL and vHIP phospho-GSK3β and phospho-mTOR, however, no differences in these protein levels were observed in the dHIP region. These data suggest that early response to electrode placement in the NAc, irrespective of whether active DBS or sham, has antidepressant-like effects in the ACTH-model of antidepressant resistance associated with distal upregulation of phospho-GSK3β and phospho-mTOR in the IL and vHIP regions of the mood network.
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- 2021
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18. Persistent motor dysfunction despite homeostatic rescue of cerebellar morphogenesis in the Car8 waddles mutant mouse
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Lauren N. Miterko, Joshua J. White, Tao Lin, Amanda M. Brown, Kevin J. O’Donovan, and Roy V. Sillitoe
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Purkinje cell ,Granule cell ,Proliferation ,Stem cells ,Lobule ,Ataxia ,Neurology. Diseases of the nervous system ,RC346-429 - Abstract
Abstract Background Purkinje cells play a central role in establishing the cerebellar circuit. Accordingly, disrupting Purkinje cell development impairs cerebellar morphogenesis and motor function. In the Car8 wdl mouse model of hereditary ataxia, severe motor deficits arise despite the cerebellum overcoming initial defects in size and morphology. Methods To resolve how this compensation occurs, we asked how the loss of carbonic anhydrase 8 (CAR8), a regulator of IP3R1 Ca2+ signaling in Purkinje cells, alters cerebellar development in Car8 wdl mice. Using a combination of histological, physiological, and behavioral analyses, we determined the extent to which the loss of CAR8 affects cerebellar anatomy, neuronal firing, and motor coordination during development. Results Our results reveal that granule cell proliferation is reduced in early postnatal mutants, although by the third postnatal week there is enhanced and prolonged proliferation, plus an upregulation of Sox2 expression in the inner EGL. Modified circuit patterning of Purkinje cells and Bergmann glia accompany these granule cell adjustments. We also find that although anatomy eventually normalizes, the abnormal activity of neurons and muscles persists. Conclusions Our data show that losing CAR8 only transiently restricts cerebellar growth, but permanently damages its function. These data support two current hypotheses about cerebellar development and disease: (1) Sox2 expression may be upregulated at sites of injury and contribute to the rescue of cerebellar structure and (2) transient delays to developmental processes may precede permanent motor dysfunction. Furthermore, we characterize waddles mutant mouse morphology and behavior during development and propose a Sox2-positive, cell-mediated role for rescue in a mouse model of human motor diseases.
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- 2019
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19. A Programmable Multi-Biomarker Neural Sensor for Closed-Loop DBS
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Mahboubeh Parastarfeizabadi, Abbas Z. Kouzani, Jaclyn Beckinghausen, Tao Lin, and Roy V. Sillitoe
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Circuits ,closed-loop ,multiple biomarkers ,neural sensor ,programmable ,Electrical engineering. Electronics. Nuclear engineering ,TK1-9971 - Abstract
Most of the current closed-loop deep brain stimulation (DBS) devices use a single biomarker in their feedback loop, which may limit their performance and applications. This paper presents the design, fabrication, and validation of a programmable multi-biomarker neural sensor which can be integrated into closed-loop DBS devices. The device is capable of sensing a combination of low-frequency (7–45 Hz), and high-frequency (200–1000 Hz) neural signals. The signals can be amplified with a digitally programmable gain within the range of 50–100 dB. The neural signals can be stored into a local memory for processing and validation. The sensing and storage functions are implemented via a combination of analog and digital circuits involving pre-amplifiers, filters, programmable post-amplifiers, microcontroller, digital potentiometer, and flash memory. The device is fabricated, and its performance is validated through: 1) bench tests using sinusoidal and pre-recorded neural signals; 2) in-vitro tests using pre-recorded neural signals in saline solution; and 3) in-vivo tests by recording neural signals from freely moving laboratory mice. The animals were implanted with a PlasticsOne electrode, and recording was conducted after recovery from the electrode implantation surgery. The experimental results are presented and discussed confirming the successful operation of the device. The size and weight of the device enable tetherless back-mountable use in pre-clinical trials.
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- 2019
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20. Loss of cerebellar function selectively affects intrinsic rhythmicity of eupneic breathing
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Yu Liu, Shuhua Qi, Fridtjof Thomas, Brittany L. Correia, Angela P. Taylor, Roy V. Sillitoe, and Detlef H. Heck
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respiration ,motor skills disorder ,ataxia ,arrhythmia ,cerebellum ,Science ,Biology (General) ,QH301-705.5 - Abstract
Respiration is controlled by central pattern generating circuits in the brain stem, whose activity can be modulated by inputs from other brain areas to adapt respiration to autonomic and behavioral demands. The cerebellum is known to be part of the neuronal circuitry activated during respiratory challenges, such as hunger for air, but has not been found to be involved in the control of spontaneous, unobstructed breathing (eupnea). Here we applied a measure of intrinsic rhythmicity, the CV2, which evaluates the similarity of subsequent intervals and is thus sensitive to changes in rhythmicity at the temporal resolution of individual respiratory intervals. The variability of intrinsic respiratory rhythmicity was reduced in a mouse model of cerebellar ataxia compared to their healthy littermates. Irrespective of that difference, the average respiratory rate and the average coefficient of variation (CV) were comparable between healthy and ataxic mice. We argue that these findings are consistent with a proposed role of the cerebellum in modulating the duration of individual respiratory intervals, which could serve the purpose of coordinating respiration with other rhythmic orofacial movements, such as fluid licking and swallowing.
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- 2020
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21. Eph/ephrin Function Contributes to the Patterning of Spinocerebellar Mossy Fibers Into Parasagittal Zones
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Elizabeth P. Lackey and Roy V. Sillitoe
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cerebellum ,mossy fiber ,Purkinje cells ,development ,patterning ,zebrinll ,Neurosciences. Biological psychiatry. Neuropsychiatry ,RC321-571 - Abstract
Purkinje cell microcircuits perform diverse functions using widespread inputs from the brain and spinal cord. The formation of these functional circuits depends on developmental programs and molecular pathways that organize mossy fiber afferents from different sources into a complex and precisely patterned map within the granular layer of the cerebellum. During development, Purkinje cell zonal patterns are thought to guide mossy fiber terminals into zones. However, the molecular mechanisms that mediate this process remain unclear. Here, we used knockout mice to test whether Eph/ephrin signaling controls Purkinje cell-mossy fiber interactions during cerebellar circuit formation. Loss of ephrin-A2 and ephrin-A5 disrupted the patterning of spinocerebellar terminals into discrete zones. Zone territories in the granular layer that normally have limited spinocerebellar input contained ectopic terminals in ephrin-A2−/−;ephrin-A5−/− double knockout mice. However, the overall morphology of the cerebellum, lobule position, and Purkinje cell zonal patterns developed normally in the ephrin-A2−/−;ephrin-A5−/− mutant mice. This work suggests that communication between Purkinje cell zones and mossy fibers during postnatal development allows contact-dependent molecular cues to sharpen the innervation of sensory afferents into functional zones.
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- 2020
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22. In vivo cerebellar circuit function is disrupted in an mdx mouse model of Duchenne muscular dystrophy
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Trace L. Stay, Lauren N. Miterko, Marife Arancillo, Tao Lin, and Roy V. Sillitoe
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duchenne muscular dystrophy ,mdx mice ,cerebellum ,purkinje cell ,cerebellar nuclei ,circuitry ,in vivo electrophysiology ,Medicine ,Pathology ,RB1-214 - Abstract
Duchenne muscular dystrophy (DMD) is a debilitating and ultimately lethal disease involving progressive muscle degeneration and neurological dysfunction. DMD is caused by mutations in the dystrophin gene, which result in extremely low or total loss of dystrophin protein expression. In the brain, dystrophin is heavily localized to cerebellar Purkinje cells, which control motor and non-motor functions. In vitro experiments in mouse Purkinje cells revealed that loss of dystrophin leads to low firing rates and high spiking variability. However, it is still unclear how the loss of dystrophin affects cerebellar function in the intact brain. Here, we used in vivo electrophysiology to record Purkinje cells and cerebellar nuclear neurons in awake and anesthetized female mdx (also known as Dmd) mice. Purkinje cell simple spike firing rate is significantly lower in mdx mice compared to controls. Although simple spike firing regularity is not affected, complex spike regularity is increased in mdx mutants. Mean firing rate in cerebellar nuclear neurons is not altered in mdx mice, but their local firing pattern is irregular. Based on the relatively well-preserved cytoarchitecture in the mdx cerebellum, our data suggest that faulty signals across the circuit between Purkinje cells and cerebellar nuclei drive the abnormal firing activity. The in vivo requirements of dystrophin during cerebellar circuit communication could help explain the motor and cognitive anomalies seen in individuals with DMD. This article has an associated First Person interview with the first author of the paper.
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- 2020
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23. Functional Outcomes of Cerebellar Malformations
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Jason S. Gill and Roy V. Sillitoe
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cerebellum ,development ,Purkinje cell ,cerebellar nuclei ,circuitry ,motor ,Neurosciences. Biological psychiatry. Neuropsychiatry ,RC321-571 - Abstract
The cerebellum is well-established as a primary center for controlling sensorimotor functions. However, recent experiments have demonstrated additional roles for the cerebellum in higher-order cognitive functions such as language, emotion, reward, social behavior, and working memory. Based on the diversity of behaviors that it can influence, it is therefore not surprising that cerebellar dysfunction is linked to motor diseases such as ataxia, dystonia, tremor, and Parkinson’s disease as well to non-motor disorders including autism spectrum disorders (ASD), schizophrenia, depression, and anxiety. Regardless of the condition, there is a growing consensus that developmental disturbances of the cerebellum may be a central culprit in triggering a number of distinct pathophysiological processes. Here, we consider how cerebellar malformations and neuronal circuit wiring impact brain function and behavior during development. We use the cerebellum as a model to discuss the expanding view that local integrated brain circuits function within the context of distributed global networks to communicate the computations that drive complex behavior. We highlight growing concerns that neurological and neuropsychiatric diseases with severe behavioral outcomes originate from developmental insults to the cerebellum.
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- 2019
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24. Genetic silencing of olivocerebellar synapses causes dystonia-like behaviour in mice
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Joshua J. White and Roy V. Sillitoe
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Science - Abstract
Dystonia is thought to be driven by impairments in cerebellar signalling. The authors use a mouse genetic approach to silence excitatory transmission in the inferior olive to cerebellum pathway, resulting in dystonia-like signs in the animals which can be alleviated using DBS stimulation of the pathway.
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- 2017
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25. Cerebellar Lobulus Simplex and Crus I Differentially Represent Phase and Phase Difference of Prefrontal Cortical and Hippocampal Oscillations
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Samuel S. McAfee, Yu Liu, Roy V. Sillitoe, and Detlef H. Heck
- Subjects
Biology (General) ,QH301-705.5 - Abstract
Summary: The cerebellum has long been implicated in tasks involving precise temporal control, especially in the coordination of movements. Here we asked whether the cerebellum represents temporal aspects of oscillatory neuronal activity, measured as instantaneous phase and difference between instantaneous phases of oscillations in two cerebral cortical areas involved in cognitive function. We simultaneously recorded Purkinje cell (PC) single-unit spike activity in cerebellar lobulus simplex (LS) and Crus I and local field potential (LFP) activity in the medial prefrontal cortex (mPFC) and dorsal hippocampus CA1 region (dCA1). Purkinje cells in cerebellar LS and Crus I differentially represented specific phases and phase differences of mPFC and dCA1 LFP oscillations in a frequency-specific manner, suggesting a site- and frequency-specific cerebellar representation of temporal aspects of neuronal oscillations in non-motor cerebral cortical areas. These findings suggest that cerebellar interactions with cerebral cortical areas involved in cognitive functions might involve temporal coordination of neuronal oscillations. : The cerebellum has long been implicated in tasks involving precise temporal control, especially in the coordination of movements. McAfee et al. show that the cerebellar principal neurons, Purkinje cells, represent precise temporal information about the phase and phase differences of neuronal oscillations occurring in two non-motor-related cerebral cortical structures. Keywords: neuronal oscillation, cerebro-cerebellar interaction, oscillation phase, phase difference
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- 2019
- Full Text
- View/download PDF
26. Shaping Diversity Into the Brain’s Form and Function
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Lauren N. Miterko, Elizabeth P. Lackey, Detlef H. Heck, and Roy V. Sillitoe
- Subjects
neuron ,glia ,folding ,layering ,connectivity ,topography ,Neurosciences. Biological psychiatry. Neuropsychiatry ,RC321-571 - Abstract
The brain contains a large diversity of unique cell types that use specific genetic programs to control development and instruct the intricate wiring of sensory, motor, and cognitive brain regions. In addition to their cellular diversity and specialized connectivity maps, each region’s dedicated function is also expressed in their characteristic gross external morphologies. The folds on the surface of the cerebral cortex and cerebellum are classic examples. But, to what extent does structure relate to function and at what spatial scale? We discuss the mechanisms that sculpt functional brain maps and external morphologies. We also contrast the cryptic structural defects in conditions such as autism spectrum disorders to the overt microcephaly after Zika infections, taking into consideration that both diseases disrupt proper cognitive development. The data indicate that dynamic processes shape all brain areas to fit into jigsaw-like patterns. The patterns in each region reflect circuit connectivity, which ultimately supports local signal processing and accomplishes multi-areal integration of information processing to optimize brain functions.
- Published
- 2018
- Full Text
- View/download PDF
27. Pathogenesis of severe ataxia and tremor without the typical signs of neurodegeneration
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Joshua J. White, Marife Arancillo, Annesha King, Tao Lin, Lauren N. Miterko, Samrawit A. Gebre, and Roy V. Sillitoe
- Subjects
Ataxia ,Tremor ,Neurodegeneration ,In vivo electrophysiology ,Behavior ,Cerebellum ,Neurosciences. Biological psychiatry. Neuropsychiatry ,RC321-571 - Abstract
Neurological diseases are especially devastating when they involve neurodegeneration. Neuronal destruction is widespread in cognitive disorders such as Alzheimer's and regionally localized in motor disorders such as Parkinson's, Huntington's, and ataxia. But, surprisingly, the onset and progression of these diseases can occur without neurodegeneration. To understand the origins of diseases that do not have an obvious neuropathology, we tested how loss of CAR8, a regulator of IP3R1-mediated Ca2+-signaling, influences cerebellar circuit formation and neural function as movement deteriorates. We found that faulty molecular patterning, which shapes functional circuits called zones, leads to alterations in cerebellar wiring and Purkinje cell activity, but not to degeneration. Rescuing Purkinje cell function improved movement and reducing their Ca2+ influx eliminated ectopic zones. Our findings in Car8wdl mutant mice unveil a pathophysiological mechanism that may operate broadly to impact motor and non-motor conditions that do not involve degeneration.
- Published
- 2016
- Full Text
- View/download PDF
28. Recent advances in understanding the mechanisms of cerebellar granule cell development and function and their contribution to behavior [version 1; referees: 3 approved]
- Author
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Elizabeth P. Lackey, Detlef H. Heck, and Roy V. Sillitoe
- Subjects
Medicine ,Science - Abstract
The cerebellum is the focus of an emergent series of debates because its circuitry is now thought to encode an unexpected level of functional diversity. The flexibility that is built into the cerebellar circuit allows it to participate not only in motor behaviors involving coordination, learning, and balance but also in non-motor behaviors such as cognition, emotion, and spatial navigation. In accordance with the cerebellum’s diverse functional roles, when these circuits are altered because of disease or injury, the behavioral outcomes range from neurological conditions such as ataxia, dystonia, and tremor to neuropsychiatric conditions, including autism spectrum disorders, schizophrenia, and attention-deficit/hyperactivity disorder. Two major questions arise: what types of cells mediate these normal and abnormal processes, and how might they accomplish these seemingly disparate functions? The tiny but numerous cerebellar granule cells may hold answers to these questions. Here, we discuss recent advances in understanding how the granule cell lineage arises in the embryo and how a stem cell niche that replenishes granule cells influences wiring when the postnatal cerebellum is injured. We discuss how precisely coordinated developmental programs, gene expression patterns, and epigenetic mechanisms determine the formation of synapses that integrate multi-modal inputs onto single granule cells. These data lead us to consider how granule cell synaptic heterogeneity promotes sensorimotor and non-sensorimotor signals in behaving animals. We discuss evidence that granule cells use ultrafast neurotransmission that can operate at kilohertz frequencies. Together, these data inspire an emerging view for how granule cells contribute to the shaping of complex animal behaviors.
- Published
- 2018
- Full Text
- View/download PDF
29. Motor Circuit Abnormalities During Cerebellar Development
- Author
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Elizabeth P. Lackey, Alejandro G. Rey Hipolito, and Roy V. Sillitoe
- Published
- 2023
30. Physiology of Dystonia: Animal Studies
- Author
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Alejandro G. Rey Hipolito, Meike E. van der Heijden, and Roy V. Sillitoe
- Published
- 2023
31. Causal Evidence for a Role of Cerebellar Lobulus Simplex in Prefrontal-Hippocampal Interaction in Spatial Working Memory Decision-Making
- Author
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Yu Liu, Samuel S. McAfee, Meike E. Van Der Heijden, Mukesh Dhamala, Roy V. Sillitoe, and Detlef H. Heck
- Subjects
Cerebellar Cortex ,Mice ,Memory, Short-Term ,Neurology ,Animals ,Prefrontal Cortex ,Neurology (clinical) ,Hippocampus ,Article ,Spatial Memory - Abstract
Spatial working memory (SWM) is a cerebrocerebellar cognitive skill supporting survival-relevant behaviors, such as optimizing foraging behavior by remembering recent routes and visited sites. It is known that SWM decision-making in rodents requires the medial prefrontal cortex (mPFC) and dorsal hippocampus. The decision process in SWM tasks carries a specific electrophysiological signature of a brief, decision-related increase in neuronal communication in the form of an increase in the coherence of neuronal theta oscillations (4-12 Hz) between the mPFC and dorsal hippocampus, a finding we replicated here during spontaneous exploration of a plus maze in freely moving mice. We further evaluated SWM decision-related coherence changes within frequency bands above theta. Decision-related coherence increases occurred in seven frequency bands between 4 and 200 Hz and decision-outcome-related differences in coherence modulation occurred within the beta and gamma frequency bands and in higher frequency oscillations up to 130 Hz. With recent evidence that Purkinje cells in the cerebellar lobulus simplex (LS) represent information about the phase and phase differences of gamma oscillations in the mPFC and dorsal hippocampus, we hypothesized that LS might be involved in the modulation of mPFC-hippocampal gamma coherence. We show that optical stimulation of LS significantly impairs SWM performance and decision-related mPFC-dCA1 coherence modulation, providing causal evidence for an involvement of cerebellar LS in SWM decision-making at the behavioral and neuronal level. Our findings suggest that the cerebellum might contribute to SWM decision-making by optimizing the decision-related modulation of mPFC-dCA1 coherence.
- Published
- 2022
32. Cerebellar Dysfunction as a Source of Dystonic Phenotypes in Mice
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Amanda M. Brown, Meike E. van der Heijden, H. A. Jinnah, and Roy V. Sillitoe
- Subjects
Neurology ,Neurology (clinical) - Abstract
There is now a substantial amount of compelling evidence demonstrating that the cerebellum may be a central locus in dystonia pathogenesis. Studies using spontaneous genetic mutations in rats and mice, engineered genetic alleles in mice, shRNA knockdown in mice, and conditional genetic silencing of fast neurotransmission in mice have all uncovered a common set of behavioral and electrophysiological defects that point to cerebellar cortical and cerebellar nuclei dysfunction as a source of dystonic phenotypes. Here, we revisit the Ptf1aCre/+;Vglut2flox/flox mutant mouse to define fundamental phenotypes and measures that are valuable for testing the cellular, circuit, and behavioral mechanisms that drive dystonia. In this model, excitatory neurotransmission from climbing fibers is genetically eliminated and, as a consequence, Purkinje cell and cerebellar nuclei firing are altered in vivo, with a prominent and lasting irregular burst pattern of spike activity in cerebellar nuclei neurons. The resulting impact on behavior is that the mice have developmental abnormalities, including twisting of the limbs and torso. These behaviors continue into adulthood along with a tremor, which can be measured with a tremor monitor or EMG. Importantly, expression of dystonic behavior is reduced upon cerebellar-targeted deep brain stimulation. The presence of specific combinations of disease-like features and therapeutic responses could reveal the causative mechanisms of different types of dystonia and related conditions. Ultimately, an emerging theme places cerebellar dysfunction at the center of a broader dystonia brain network.
- Published
- 2022
33. Motor control: Internalizing your place in the world
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Meike E. van der Heijden, Amanda M. Brown, and Roy V. Sillitoe
- Subjects
General Agricultural and Biological Sciences ,General Biochemistry, Genetics and Molecular Biology - Published
- 2021
34. Neuromodulation of the cerebellum rescues movement in a mouse model of ataxia
- Author
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Joy Zhou, Joshua J. White, Lauren N. Miterko, Meike E van der Heijden, Jaclyn Beckinghausen, Tao Lin, and Roy V. Sillitoe
- Subjects
Male ,0301 basic medicine ,Cerebellum ,Ataxia ,Deep brain stimulation ,Movement disorders ,Cerebellar Ataxia ,Movement ,medicine.medical_treatment ,Science ,Purkinje cell ,General Physics and Astronomy ,Nerve Tissue Proteins ,Stimulation ,Neurotransmission ,Synaptic Transmission ,behavioral disciplines and activities ,Article ,General Biochemistry, Genetics and Molecular Biology ,Mice ,Purkinje Cells ,03 medical and health sciences ,0302 clinical medicine ,Biomarkers, Tumor ,medicine ,Animals ,Multidisciplinary ,business.industry ,Parkinson Disease ,General Chemistry ,Neuromodulation (medicine) ,nervous system diseases ,Disease Models, Animal ,030104 developmental biology ,medicine.anatomical_structure ,surgical procedures, operative ,Cerebellar Nuclei ,nervous system ,Female ,Spinocerebellar ataxia ,medicine.symptom ,business ,Neuroscience ,therapeutics ,030217 neurology & neurosurgery - Abstract
Deep brain stimulation (DBS) relieves motor dysfunction in Parkinson’s disease, and other movement disorders. Here, we demonstrate the potential benefits of DBS in a model of ataxia by targeting the cerebellum, a major motor center in the brain. We use the Car8 mouse model of hereditary ataxia to test the potential of using cerebellar nuclei DBS plus physical activity to restore movement. While low-frequency cerebellar DBS alone improves Car8 mobility and muscle function, adding skilled exercise to the treatment regimen additionally rescues limb coordination and stepping. Importantly, the gains persist in the absence of further stimulation. Because DBS promotes the most dramatic improvements in mice with early-stage ataxia, we postulated that cerebellar circuit function affects stimulation efficacy. Indeed, genetically eliminating Purkinje cell neurotransmission blocked the ability of DBS to reduce ataxia. These findings may be valuable in devising future DBS strategies., Deep brain stimulation (DBS) has potential for several movement disorders. Here the authors show that DBS improves motor function in a mouse model of ataxia.
- Published
- 2021
35. Abnormal cerebellar function and tremor in a mouse model for non‐manifesting partially penetrant dystonia type 6
- Author
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Roy V. Sillitoe, Dominic J Kizek, Ross Perez, Elena K Ruff, Meike E van der Heijden, and Michelle E. Ehrlich
- Subjects
0301 basic medicine ,Cerebellum ,Physiology ,Thalamus ,Biology ,medicine.disease_cause ,Article ,Mice ,03 medical and health sciences ,0302 clinical medicine ,Tremor ,medicine ,Animals ,Humans ,Dystonia ,Mutation ,Nuclear Proteins ,Heterozygote advantage ,medicine.disease ,Action tremor ,DNA-Binding Proteins ,Electrophysiology ,030104 developmental biology ,medicine.anatomical_structure ,nervous system ,Excitatory postsynaptic potential ,Apoptosis Regulatory Proteins ,Neuroscience ,030217 neurology & neurosurgery - Abstract
Key points Loss-of-function mutations in the Thap1 gene cause partially penetrant dystonia type 6 (DYT6). Some non-manifesting DYT6 mutation carriers have tremor and abnormal cerebello-thalamo-cortical signalling. We show that Thap1 heterozygote mice have action tremor, a reduction in cerebellar neuron number, and abnormal electrophysiological signals in the remaining neurons. These results underscore the importance of Thap1 levels for cerebellar function. These results uncover how cerebellar abnormalities contribute to different dystonia-associated motor symptoms. Abstract Loss-of-function mutations in the Thanatos-associated domain-containing apoptosis-associated protein 1 (THAP1) gene cause partially penetrant autosomal dominant dystonia type 6 (DYT6). However, the neural abnormalities that promote the resultant motor dysfunctions remain elusive. Studies in humans show that some non-manifesting DYT6 carriers have altered cerebello-thalamo-cortical function with subtle but reproducible tremor. Here, we uncover that Thap1 heterozygote mice have action tremor that rises above normal baseline values even though they do not exhibit overt dystonia-like twisting behaviour. At the neural circuit level, we show using in vivo recordings in awake Thap1+/- mice that Purkinje cells have abnormal firing patterns and that cerebellar nuclei neurons, which connect the cerebellum to the thalamus, fire at a lower frequency. Although the Thap1+/- mice have fewer Purkinje cells and cerebellar nuclei neurons, the number of long-range excitatory outflow projection neurons is unaltered. The preservation of interregional connectivity suggests that abnormal neural function rather than neuron loss instigates the network dysfunction and the tremor in Thap1+/- mice. Accordingly, we report an inverse correlation between the average firing rate of cerebellar nuclei neurons and tremor power. Our data show that cerebellar circuitry is vulnerable to Thap1 mutations and that cerebellar dysfunction may be a primary cause of tremor in non-manifesting DYT6 carriers and a trigger for the abnormal postures in manifesting patients.
- Published
- 2021
36. Abnormal Cerebellar Development in Autism Spectrum Disorders
- Author
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Jason S. Gill, Meike E van der Heijden, and Roy V. Sillitoe
- Subjects
Cerebellum ,Autism Spectrum Disorder ,Concordance ,behavioral disciplines and activities ,Dizygotic twins ,Article ,03 medical and health sciences ,0302 clinical medicine ,Developmental Neuroscience ,mental disorders ,medicine ,Humans ,Symptom onset ,Risk factor ,business.industry ,Cerebellar function ,Brain ,Infant ,Cognition ,medicine.disease ,030227 psychiatry ,medicine.anatomical_structure ,nervous system ,Neurology ,Autism ,business ,Neuroscience ,030217 neurology & neurosurgery - Abstract
Autism spectrum disorders (ASD) comprise a group of heterogeneous neurodevelopmental conditions characterized by impaired social interactions and repetitive behaviors with symptom onset in early infancy. The genetic risks for ASD have long been appreciated: concordance of ASD diagnosis may be as high as 90% for monozygotic twins and 30% for dizygotic twins, and hundreds of mutations in single genes have been associated with ASD. Nevertheless, only 5–30% of ASD cases can be explained by a known genetic cause, suggesting that genetics is not the only factor at play. More recently, several studies reported that up to 40% of infants with cerebellar hemorrhages and lesions are diagnosed with ASD. These hemorrhages are overrepresented in severely premature infants, who are born during a period of highly dynamic cerebellar development that encompasses an approximately 5-fold size expansion, an increase in structural complexity, and remarkable rearrangements of local neural circuits. The incidence of ASD-causing cerebellar hemorrhages during this window supports the hypothesis that abnormal cerebellar development may be a primary risk factor for ASD. However, the links between developmental deficits in the cerebellum and the neurological dysfunctions underlying ASD are not completely understood. Here, we discuss key processes in cerebellar development, what happens to the cerebellar circuit when development is interrupted, and how impaired cerebellar function leads to social and cognitive impairments. We explore a central question: Is cerebellar development important for the generation of the social and cognitive brain or is the cerebellum part of the social and cognitive brain itself?
- Published
- 2021
37. Disruption of the ATXN1-CIC complex reveals the role of additional nuclear ATXN1 interactors in spinocerebellar ataxia type 1
- Author
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Stephanie L. Coffin, Mark A. Durham, Larissa Nitschke, Eder Xhako, Amanda M. Brown, Jean-Pierre Revelli, Esmeralda Villavicencio Gonzalez, Tao Lin, Hillary P. Handler, Yanwan Dai, Alexander J. Trostle, Ying-Wooi Wan, Zhandong Liu, Roy V. Sillitoe, Harry T. Orr, and Huda Y. Zoghbi
- Subjects
General Neuroscience - Abstract
Spinocerebellar ataxia type 1 (SCA1) is a paradigmatic neurodegenerative disease in that it is caused by a mutation in a broadly expressed protein, ATXN1; however, only select populations of cells degenerate. The interaction of polyglutamine-expanded ATXN1 with the transcriptional repressor CIC drives cerebellar Purkinje cell pathogenesis; however, the importance of this interaction in other vulnerable cells remains unknown. Here, we mutated the 154Q knockin allele of Atxn1
- Published
- 2023
38. Ankyrin-R Links Kv3.3 to the Spectrin Cytoskeleton and Is Required for Purkinje Neuron Survival
- Author
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Roy V. Sillitoe, Matthew N. Rasband, Tao Lin, Sharon R. Stevens, Meike E van der Heijden, and Yuki Ogawa
- Subjects
Ankyrins ,Male ,Cerebellum ,Ataxia ,Cell Survival ,macromolecular substances ,Mice ,Purkinje Cells ,ANK1 ,medicine ,Ankyrin ,Animals ,Spinocerebellar Ataxias ,Spectrin ,Cytoskeleton ,Research Articles ,chemistry.chemical_classification ,General Neuroscience ,medicine.disease ,Cell biology ,medicine.anatomical_structure ,nervous system ,chemistry ,Shaw Potassium Channels ,Spinocerebellar ataxia ,Female ,medicine.symptom ,Protein stabilization - Abstract
Ankyrin scaffolding proteins are critical for membrane domain organization and protein stabilization in many different cell types including neurons. In the cerebellum, Ankyrin-R (AnkR) is highly enriched in Purkinje neurons, granule cells, and in the cerebellar nuclei (CN). Using male and female mice with a floxed allele forAnk1in combination withNestin-CreandPcp2-Cremice, we found that ablation of AnkR from Purkinje neurons caused ataxia, regional and progressive neurodegeneration, and altered cerebellar output. We show that AnkR interacts with the cytoskeletal protein β3 spectrin and the potassium channel Kv3.3. Loss of AnkR reduced somatic membrane levels of β3 spectrin and Kv3.3 in Purkinje neurons. Thus, AnkR links Kv3.3 channels to the β3 spectrin-based cytoskeleton. Our results may help explain why mutations in β3 spectrin and Kv3.3 both cause spinocerebellar ataxia.SIGNIFICANCE STATEMENTAnkyrin scaffolding proteins localize and stabilize ion channels in the membrane by linking them to the spectrin-based cytoskeleton. Here, we show that Ankyrin-R (AnkR) links Kv3.3 K+channels to the β3 spectrin-based cytoskeleton in Purkinje neurons. Loss of AnkR causes Purkinje neuron degeneration, altered cerebellar physiology, and ataxia, which is consistent with mutations in Kv3.3 and β3 spectrin causing spinocerebellar ataxia.
- Published
- 2022
39. Editor's evaluation: Cerebellar modulation of memory encoding in the periaqueductal grey and fear behaviour
- Author
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Roy V Sillitoe
- Published
- 2022
40. Decision letter: Cerebellar modulation of memory encoding in the periaqueductal grey and fear behaviour
- Author
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Roy V Sillitoe and Detlef Heck
- Published
- 2022
41. Silencing the Output of Cerebellar Neurons Using Cell Type-Specific Genetic Deletion of Vesicular GABA and Glutamate Transporters
- Author
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Meike E. van der Heijden, Amanda M. Brown, and Roy V. Sillitoe
- Published
- 2022
42. Proceedings of the 10th annual deep brain stimulation think tank: Advances in cutting edge technologies, artificial intelligence, neuromodulation, neuroethics, interventional psychiatry, and women in neuromodulation
- Author
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Joshua K. Wong, Helen S. Mayberg, Doris D. Wang, R. Mark Richardson, Casey H. Halpern, Lothar Krinke, Mattia Arlotti, Lorenzo Rossi, Alberto Priori, Sara Marceglia, Ro’ee Gilron, James F. Cavanagh, Jack W. Judy, Svjetlana Miocinovic, Annaelle D. Devergnas, Roy V. Sillitoe, Stephanie Cernera, Carina R. Oehrn, Aysegul Gunduz, Wayne K. Goodman, Erika A. Petersen, Helen Bronte-Stewart, Robert S. Raike, Mahsa Malekmohammadi, David Greene, Petra Heiden, Huiling Tan, Jens Volkmann, Valerie Voon, Luming Li, Pankaj Sah, Terry Coyne, Peter A. Silburn, Cynthia S. Kubu, Anna Wexler, Jennifer Chandler, Nicole R. Provenza, Sarah R. Heilbronner, Marta San Luciano, Christopher J. Rozell, Michael D. Fox, Coralie de Hemptinne, Jaimie M. Henderson, Sameer A. Sheth, Michael S. Okun, Henderson, Jaimie M [0000-0002-3276-2267], and Apollo - University of Cambridge Repository
- Subjects
Assistive Technology ,Depression ,Parkinson's disease ,Rehabilitation ,Neurosciences ,Bioengineering ,Experimental Psychology ,artificial intelligence ,deep brain stimulation ,neuroethics ,Behavioral Neuroscience ,Psychiatry and Mental health ,Neuropsychology and Physiological Psychology ,Mental Health ,Neurology ,Parkinson’s disease ,Psychology ,epilepsy ,Cognitive Sciences ,adaptive DBS ,interventional psychiatry ,dystonia ,deep brain stimulation (DBS) ,Biological Psychiatry - Abstract
The deep brain stimulation (DBS) Think Tank X was held on August 17–19, 2022 in Orlando FL. The session organizers and moderators were all women with the theme women in neuromodulation. Dr. Helen Mayberg from Mt. Sinai, NY was the keynote speaker. She discussed milestones and her experiences in developing depression DBS. The DBS Think Tank was founded in 2012 and provides an open platform where clinicians, engineers and researchers (from industry and academia) can freely discuss current and emerging DBS technologies as well as the logistical and ethical issues facing the field. The consensus among the DBS Think Tank X speakers was that DBS has continued to expand in scope however several indications have reached the “trough of disillusionment.” DBS for depression was considered as “re-emerging” and approaching a slope of enlightenment. DBS for depression will soon re-enter clinical trials. The group estimated that globally more than 244,000 DBS devices have been implanted for neurological and neuropsychiatric disorders. This year’s meeting was focused on advances in the following areas: neuromodulation in Europe, Asia, and Australia; cutting-edge technologies, closed loop DBS, DBS tele-health, neuroethics, lesion therapy, interventional psychiatry, and adaptive DBS.
- Published
- 2022
43. Zones and Stripes: Development of Cerebellar Topography
- Author
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Lauren N. Miterko, Roy V. Sillitoe, and Richard Hawkes
- Published
- 2021
44. The cerebellum contributes to tonic-clonic seizures by altering neuronal activity in the ventral posteromedial nucleus (VPM) of the thalamus
- Author
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Joshua Ortiz-Guzman, Benjamin R. Arenkiel, Jaclyn Beckinghausen, Roy V. Sillitoe, Detlef H. Heck, Yu Liu, Benjamin J. Bachman, and Tao Lin
- Subjects
Cerebellum ,Lidocaine ,business.industry ,Thalamus ,Optogenetics ,Ventral posteromedial nucleus ,Electrophysiology ,medicine.anatomical_structure ,Tonic-clonic seizures ,medicine ,Premovement neuronal activity ,business ,Neuroscience ,medicine.drug - Abstract
SummaryThalamo-cortical networks are central to seizures, yet it’s unclear how these circuits initiate the seizures. Here, we test the hypothesis that a facial region of the thalamus, the VPM, is a source of convulsive, tonic-clonic seizures. We devised an in vivo optogenetic mouse model to elicit tonic-clonic seizures by driving convergent input to the VPM. With viral tracing, we show dense cerebellar and cerebral cortical afferent input to the VPM. Lidocaine microinfusions into the cerebellar nuclei selectively block seizure initiation. We perform single-unit electrophysiology recordings during awake, convulsive seizures to define the local activity of thalamic neurons before, during, and after seizure onset. We find highly dynamic activity with biphasic properties, raising the possibility that heterogenous activity patterns promote seizures. These data reveal the VPM as a source of tonic-clonic seizures, with cerebellar input providing the predominant signals.
- Published
- 2021
45. Author response: Maturation of Purkinje cell firing properties relies on neurogenesis of excitatory neurons
- Author
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Tao Lin, Ross Perez, Amanda M Brown, Fatma S Ișleyen, Roy V. Sillitoe, Elizabeth P. Lackey, Huda Y. Zoghbi, Meike E van der Heijden, and Sarah G Donofrio
- Subjects
medicine.anatomical_structure ,Neurogenesis ,Purkinje cell ,medicine ,Excitatory postsynaptic potential ,Biology ,Neuroscience - Published
- 2021
46. Current Opinions and Consensus for Studying Tremor in Animal Models
- Author
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Lauren N. Miterko, Phyllis L. Faust, Martin J. Gallagher, Sheng-Han Kuo, Ming Kai Pan, Elan D. Louis, Murni Tio, Stefan M. Pulst, Su youne Chang, Adrian Handforth, Kyle A. Lyman, Billur Avlar, Roy V. Sillitoe, Dane M. Chetkovich, Eng-King Tan, Collin J. Anderson, Rodger J. Elble, Amanda M Brown, Lorraine N. Clark, and Eric J. Lang
- Subjects
medicine.medical_specialty ,Consensus ,Neurology ,Swine ,Article ,050105 experimental psychology ,Mice ,03 medical and health sciences ,0302 clinical medicine ,Neuroimaging ,Tremor ,Animals ,Medicine ,0501 psychology and cognitive sciences ,Expert Testimony ,business.industry ,05 social sciences ,Brain ,Haplorhini ,Rats ,nervous system diseases ,Models, Animal ,Drosophila ,Neurology (clinical) ,Nerve Net ,business ,Neuroscience ,030217 neurology & neurosurgery ,Brain circuitry - Abstract
Tremor is the most common movement disorder; however, we are just beginning to understand the brain circuitry that generates tremor. Various neuroimaging, neuropathological, and physiological studies in human tremor disorders have been performed to further our knowledge of tremor. But, the causal relationship between these observations and tremor is usually difficult to establish and detailed mechanisms are not sufficiently studied. To overcome these obstacles, animal models can provide an important means to look into human tremor disorders. In this manuscript, we will discuss the use of different species of animals (mice, rats, fruit flies, pigs, and monkeys) to model human tremor disorders. Several ways to manipulate the brain circuitry and physiology in these animal models (pharmacology, genetics, and lesioning) will also be discussed. Finally, we will discuss how these animal models can help us to gain knowledge of the pathophysiology of human tremor disorders, which could serve as a platform towards developing novel therapies for tremor.
- Published
- 2019
47. Emerging connections between cerebellar development, behaviour and complex brain disorders
- Author
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Aaron Sathyanesan, Roy V. Sillitoe, Vittorio Gallo, Joseph Scafidi, Joy Zhou, and Detlef H. Heck
- Subjects
0301 basic medicine ,Cerebellum ,Down syndrome ,Disease ,Article ,03 medical and health sciences ,0302 clinical medicine ,Intellectual disability ,Connectome ,medicine ,Animals ,Humans ,Neocortex ,business.industry ,General Neuroscience ,Cognition ,medicine.disease ,030104 developmental biology ,medicine.anatomical_structure ,nervous system ,Neurodevelopmental Disorders ,Autism spectrum disorder ,Nerve Net ,business ,Neuroscience ,030217 neurology & neurosurgery - Abstract
The human cerebellum has a protracted developmental timeline compared with the neocortex, expanding the window of vulnerability to neurological disorders. As the cerebellum is critical for motor behaviour, it is not surprising that most neurodevelopmental disorders share motor deficits as a common sequela. However, evidence gathered since the late 1980s suggests that the cerebellum is involved in motor and non-motor function, including cognition and emotion. More recently, evidence indicates that major neurodevelopmental disorders such as intellectual disability, autism spectrum disorder, attention-deficit hyperactivity disorder and Down syndrome have potential links to abnormal cerebellar development. Out of recent findings from clinical and preclinical studies, the concept of the ‘cerebellar connectome’ has emerged that can be used as a framework to link the role of cerebellar development to human behaviour, disease states and the design of better therapeutic strategies. Recent studies indicate that cerebellar dysfunction contributes to the aetiology of many neurodevelopmental disorders. In this review, Gallo and colleagues cover recent discoveries in basic cerebellar research, linking them to human imaging and preclinical work on complex brain disorders with motor and non-motor deficits.
- Published
- 2019
48. Persistent motor dysfunction despite homeostatic rescue of cerebellar morphogenesis in the Car8 waddles mutant mouse
- Author
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Roy V. Sillitoe, Amanda M Brown, Tao Lin, Lauren N. Miterko, Joshua J. White, and Kevin J. O'Donovan
- Subjects
0301 basic medicine ,Cerebellum ,Ataxia ,Purkinje cell ,Proliferation ,Morphogenesis ,Mice, Transgenic ,Nerve Tissue Proteins ,Stem cells ,Biology ,lcsh:RC346-429 ,Mice ,Purkinje Cells ,03 medical and health sciences ,0302 clinical medicine ,Developmental Neuroscience ,Granule cell ,Tremor ,Biomarkers, Tumor ,medicine ,Animals ,Homeostasis ,lcsh:Neurology. Diseases of the nervous system ,Cell Proliferation ,Movement Disorders ,Behavior, Animal ,SOXB1 Transcription Factors ,Gene Expression Regulation, Developmental ,Lobule ,Motor coordination ,Mice, Inbred C57BL ,Disease Models, Animal ,Dystonia ,030104 developmental biology ,medicine.anatomical_structure ,Animals, Newborn ,nervous system ,medicine.symptom ,Stem cell ,Developmental biology ,Neuroscience ,030217 neurology & neurosurgery ,Research Article - Abstract
Background Purkinje cells play a central role in establishing the cerebellar circuit. Accordingly, disrupting Purkinje cell development impairs cerebellar morphogenesis and motor function. In the Car8wdl mouse model of hereditary ataxia, severe motor deficits arise despite the cerebellum overcoming initial defects in size and morphology. Methods To resolve how this compensation occurs, we asked how the loss of carbonic anhydrase 8 (CAR8), a regulator of IP3R1 Ca2+ signaling in Purkinje cells, alters cerebellar development in Car8wdl mice. Using a combination of histological, physiological, and behavioral analyses, we determined the extent to which the loss of CAR8 affects cerebellar anatomy, neuronal firing, and motor coordination during development. Results Our results reveal that granule cell proliferation is reduced in early postnatal mutants, although by the third postnatal week there is enhanced and prolonged proliferation, plus an upregulation of Sox2 expression in the inner EGL. Modified circuit patterning of Purkinje cells and Bergmann glia accompany these granule cell adjustments. We also find that although anatomy eventually normalizes, the abnormal activity of neurons and muscles persists. Conclusions Our data show that losing CAR8 only transiently restricts cerebellar growth, but permanently damages its function. These data support two current hypotheses about cerebellar development and disease: (1) Sox2 expression may be upregulated at sites of injury and contribute to the rescue of cerebellar structure and (2) transient delays to developmental processes may precede permanent motor dysfunction. Furthermore, we characterize waddles mutant mouse morphology and behavior during development and propose a Sox2-positive, cell-mediated role for rescue in a mouse model of human motor diseases. Electronic supplementary material The online version of this article (10.1186/s13064-019-0130-4) contains supplementary material, which is available to authorized users.
- Published
- 2019
49. Insights into cerebellar development and connectivity
- Author
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Roy V. Sillitoe and Jaclyn Beckinghausen
- Subjects
0301 basic medicine ,Cerebellum ,Ataxia ,Schizophrenia (object-oriented programming) ,Purkinje cell ,Biology ,Article ,Purkinje Cells ,03 medical and health sciences ,0302 clinical medicine ,Cerebellar Diseases ,medicine ,Animals ,Humans ,Dystonia ,General Neuroscience ,Dyslexia ,Cognition ,medicine.disease ,030104 developmental biology ,medicine.anatomical_structure ,nervous system ,Autism spectrum disorder ,medicine.symptom ,Neuroscience ,030217 neurology & neurosurgery - Abstract
The cerebellum has a well-established role in controlling motor functions such coordination, balance, posture, and skilled learning. There is mounting evidence that it might also play a critical role in non-motor functions such as cognition and emotion. It is therefore not surprising that cerebellar deficits are associated with a wide array of diseases including ataxia, dystonia tremor, schizophrenia, dyslexia, and autism spectrum disorder. What is intriguing is that a seemingly uniform circuit that is often described as being “simple” should carry out all of these behaviors. Analyses of how cerebellar circuits develop have revealed that such descriptions massively underestimate the complexity of the cerebellum. The cerebellum is in fact highly patterned and organized around a series of parasagittal stripes and transverse zones. This topographic architecture partitions all cerebellar circuits into functional modules that are thought to enhance processing power during cerebellar dependent behaviors. What are arguably the most remarkable features of cerebellar topography are the developmental processes that produce them. This review is concerned with the genetic and cellular mechanisms that orchestrate cerebellar patterning. We place a major focus on how Purkinje cells control all aspects of cerebellar circuit assembly. Using this model, we discuss evidence for how “zebra-like” patterns in Purkinje cells sculpt the cerebellum, how specific genetic cues mediate the process, and how activity refines the patterns into an adult map that is capable of executing various functions. We will also discuss how defective Purkinje cell patterning might impact the pathogenesis of neurological conditions.
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- 2019
50. Abstract 3717: KMT2D loss cooperates with PTCH loss for medulloblastoma genesis
- Author
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Shilpa S. Dhar, Calena J. Brown, Ali S. Rizvi, Janak R. Abraham, Roy V. Sillitoe, Kaifu Chen, and Min Gyu Lee
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Cancer Research ,Oncology - Abstract
We have previously reported that the histone H3 lysine 4 methyltransferase KMT2D (also called MLL4, MLL2, and ALR; a transcriptional coactivator) is required for neuronal differentiation of human neuron-committed NT2/D1 embryonal carcinoma stem cells. Notably, we have shown that brain-specific knockout of Kmt2d alone induces spontaneous medulloblastoma (MB) in mice and that Kmt2d loss in the brain highly upregulates several oncogenic signaling programs and downregulates tumor suppressor genes. Consistent with this, our analysis of several publicly available databases indicates that Kmt2d is the most frequently mutated epigenetic modifier (8%‒10%) in MB. In this study, we sought to assess whether Kmt2d loss cooperates with another oncogenic event in MB genesis. Particularly, PTCH (also known as PTCH1), a potent MB-signaling suppressor, is one of the most frequently mutated genes in MB, and KMT2D mutations co-occur with PTCH mutations more than with many other mutations in MB. Therefore, we determined the effect of Kmt2d loss on of Ptch+/--driven MB genesis by generating and analyzing Nestin-Cre Kmt2dfl/+ Ptch+/- mice. Our results showed that heterozygous loss of Kmt2d strongly increased the genesis and incidence of Ptch+/--driven MB. Supporting this, immunohistochemistry staining of Ki-67 (a proliferation marker) showed that heterozygous loss of Kmt2d in Ptch+/--driven MB highly increased the proliferation of MB cells. Our transcriptomic analysis showed that heterozygous Kmt2d loss upregulated tumor-promoting programs, including G-protein-coupled receptor signaling and oxidation-reduction process. In line with this, heterozygous Kmt2d loss upregulated oncogenic kinases (e.g., phospho-AKT1 and phospho-ERK) that may be downstream of G-protein-coupled receptor signaling. Mechanistically, our results indicate that these tumor-promoting programs are repressed, at least in part, by the transcription-repressive and tumor-suppressive factor (s) NCOR2, whose expression is activated by KMT2D. Our results would be the first to provide molecular insights into how co-losses of an epigenetic modifier and an MB-signaling suppressor cooperate for MB genesis. Our new mouse model would be helpful in future preclinical therapeutic experiments for MB treatment. Our findings suggest that targeting oncogenic effectors downstream of KMT2D loss can be considered a potential therapeutic strategy for MB treatment. Citation Format: Shilpa S. Dhar, Calena J. Brown, Ali S. Rizvi, Janak R. Abraham, Roy V. Sillitoe, Kaifu Chen, Min Gyu Lee. KMT2D loss cooperates with PTCH loss for medulloblastoma genesis [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2022; 2022 Apr 8-13. Philadelphia (PA): AACR; Cancer Res 2022;82(12_Suppl):Abstract nr 3717.
- Published
- 2022
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