Biology subjects

Bellyou, M.

Publications and source records attributed to Bellyou, M..

3 recordsLinked to original sources

bioRxiv2025

A simple, open-source restraint system for magnetic resonance imaging in awake rats

Magnetic resonance imaging (MRI) is a critical tool for translational neuroscience, offering cross-species insights into brain structure and function; however, its application in preclinical research is constrained by routine anesthesia use or sedation, which alters neural activity and limits comparisons to awake human imaging. Awake rodent functional MRI (fMRI) provides a powerful platform for investigating brain function under physiologically relevant conditions, but implementation is limited by technical challenges, particularly head motion and stress during scanning. Most restraint systems employ initial anesthesia, compromising translatability of findings, and highlighting the need for improved designs. We developed a novel restraint system optimized for awake rat fMRI. The system consists of modular 3D-printed components and can be assembled in under five minutes. It is accompanied by a protocol that includes head-post implantation followed by an 11-day habituation period post-surgical recovery. The system eliminates the need for isoflurane anesthesia, ear bars, and bite bars, reducing stress and improving animal comfort. It supports integration with behavioral paradigms such as pupil tracking and licking responses. High-resolution T2-weighted anatomical images and functional scans obtained using the system showed excellent spatial clarity and minimal motion artifacts. Quality control metrics, including head motion parameters and temporal signal-to-noise ratio, confirmed the systems stability and suitability for awake imaging. Functional connectivity analysis revealed robust positive correlations between functionally relevant regions. This system offers a scalable, reproducible, and animal-friendly solution for awake rat fMRI. While the current design limits direct cranial access for multimodal recordings, it enables high-quality, behaviorally enriched imaging without anesthesia. Significance Statement: Most rodent fMRI studies, including awake studies, rely on anesthesia, which profoundly alters brain activity and limits the interpretation of the data. This study presents a novel restraint system that enables high-quality fMRI in fully awake rats, eliminating the need for anesthesia, ear bars, and bite bars. By reducing stress and motion, this simple restraint system allows for investigation of neural activity and connectivity without confounds from sedation or anesthesia. Its open-source, modular design supports behavioral tasks and broad accessibility, making it a valuable tool for neuroscience research seeking to bridge the gap between preclinical imaging and real-world brain function.

neuroscience↗

bioRxiv2025

A non-invasive approach to awake mouse fMRI compatible with multi-modal techniques

Mouse functional magnetic resonance imaging (fMRI) studies contribute significantly to basic fundamental and translational neuroscience research. Performing fMRI in awake mice could facilitate complex tasks in the magnet and improve translational validity by avoiding anesthesia-related neural and neurovascular changes. Existing surgical approaches provide excellent motion control but are not desirable for all experiments aiming to scan awake mice. These include studies with transgenic mouse lines that are vulnerable to anesthesia or mice in longitudinal studies involving cognition. To address these needs, we propose a non-invasive restraint to scan mice in the awake state. The restraint was designed to be compatible with brain stimulation and recording approaches often combined with fMRI. It was evaluated on the basis of motion, fMRI data quality, and animal stress levels, and compared to a conventional headpost restraint. We found the proposed approach was effective at restraining mice across a broad range of weights without the need for any anesthesia for setup. The non-invasive restraint led to higher data attrition after censoring high motion volumes, but by acquiring roughly 25% more data we could obtain comparable network spatial specificity to the headpost approach. Our results demonstrate a simple open-source head restraint that can be used for awake mouse fMRI for certain cohorts, and we establish suitable acclimation and scanning protocols for use with this restraint.

neuroscience↗

bioRxiv2021

Effects of memantine and high dose vitamin D on gait in the APP/PS1 mouse model of Alzheimer's disease following vitamin D deprivation

BackgroundAltered gait is a frequent feature of Alzheimers disease (AD), as is vitamin D deficiency. Treatment with memantine and vitamin D can protect cortical axons from exposure to amyloid-{beta} and glutamate toxicity, suggesting this combination may mitigate altered gait in AD. ObjectiveInvestigate the effects of vitamin D deprivation and subsequent treatment with memantine and vitamin D enrichment on gait performance in APPswe/PS1dE9 mice. MethodsMale APPswe/PS1dE9 mice were split into four groups (n=14 each) at 2.5 months of age. A control group was fed a standard diet throughout while the other three groups started a vitamin D-deficient diet at month 6. The VitD- group remained on this deficient diet for the rest of the study. At month 9, the remaining two groups began treatment with either memantine alone or memantine combined with 10 IU/g of vitamin D. Gait performance was assessed at months 6, 9, 12, and 15. ResultsVitamin D deprivation led to a 13% increase in hind stride width by month 15 (p<0.001). Examination of the treatment groups at month 15 revealed that mice treated with memantine alone still showed an increase in hind stride width compared to controls (p<0.01), while mice treated with memantine and vitamin D did not (p=0.21). ConclusionVitamin D deprivation led to impaired postural control in the APPswe/PS1dE9 model. Treatment with memantine and vitamin D, but not memantine alone, prevented this impairment. Future work should explore the potential for treatments incorporating vitamin D supplementation to improve gait in people with AD.

animal behavior and cognition↗