Ranieri, B. | bioRxiv Science

bioRxiv2024

TrAQ: a novel, versatile, semi-automated, two-dimensional motor behavioural tracking software

We present TrAQ, a new MATLAB-based two-dimensional tracking software for Open Field video analysis of unmarked single animal, featuring minimum user intervention. We developed TrAQ with the purpose to automatically count the in-plane rotations, an important parameter in the 6-hydroxydopamine hemiparkinsonian rat model and in many rodent models of neurodegenerative diseases, a very time-consuming manual task for highly trained human operators. In addition, TrAQ allows automatic recognition of the animal within a user defined arena providing a quantitative measurement of the body centroid and the two extremities positions. A full range of quantitative kinematic behavioral parameters are automatically calculated, and the optional shape erosion feature adds usage flexibility. TrAQ, free and non-species-specific application, was quantitively tested with rodents and on a qualitative basis with zebrafish, and invertebrate animal models. Quantitative results were successfully validated against a commercial software (for tracking) and manual annotation (for rotations in an hemiparkinsonian rat model). This is a widely used model in preclinical research to study postural instability and motor asymmetry. TrAQ allows the characterization of motor asymmetry using non-invasive tools, thus appreciating the spontaneous Open Field behaviour of unmarked single animal, with minimum user intervention.

animal behavior and cognition↗

bioRxiv2022

Mapping neuroinflammation in vivo with diffusion-MRI in rats given a systemic lipopolysaccharide challenge

It is becoming increasingly apparent that neuroinflammation plays a critical role in an array of neurological and psychiatric disorders. Recent studies have demonstrated the potential of diffusion MRI (dMRI) to characterize changes in microglial density and morphology associated with neuroinflammation, but these were conducted mostly ex vivo and/or in extreme, non-physiological animal models. Here, we build upon these studies by investigating the utility of well-established dMRI methods to detect neuroinflammation in vivo in a more clinically relevant animal model of sickness behavior. We show that diffusion tensor imaging (DTI) and neurite orientation dispersion and density imaging (NODDI) indicate widespread increases in diffusivity in the brains of rats given a systemic lipopolysaccharide challenge (n=20) vs. vehicle-treated controls (n=12). These diffusivity changes correlated with histologically measured changes in microglial morphology, confirming the sensitivity of dMRI to neuroinflammatory processes. This study marks a further step towards establishing a noninvasive indicator of neuroinflammation, which would greatly facilitate early diagnosis and treatment monitoring in various neurological and psychiatric diseases.

neuroscience↗