Vidas-Guscic, N. D. | Search bioRxiv

bioRxiv2025

Mapping brain volume changes in the zQ175DN mouse model of Huntington's disease: a longitudinal MRI study

Huntingtons disease (HD) is a progressive neurodegenerative disease affecting motor and cognitive abilities, as well as exhibiting psychiatric manifestations. Studies in people with HD (PwHD) consistently report atrophy of the caudate and putamen as an early pathological event and is therefore considered an early biomarker. Investigating whether similar phenotypic features are apparent in rodent HD models is important since it could have translational potential in evaluating the efficacy of novel therapeutic strategies. We used high-resolution anatomical images to longitudinally investigate brain morphology in the zQ175DN heterozygous mouse model (HET) and wildtype littermates (WT) at 3, 6, and 10 months of age (M), which reflect different stages of phenotypic progression. We investigated volumetric alterations using semi-automatic segmentations of HD on relevant regions-of-interest (striatum, cerebellum, corpus callosum, cerebral cortex, ventricles, and total brain volume) and whole brain voxel-wise Tensor Based Morphometry (TBM) analysis. The striatum showed the earliest progressive lower absolute volume in HET mice compared to WT, starting from 3M, followed by lower absolute volume of cortex and corpus callosum concomitantly at 6 and 10M. TBM highlighted lower relative local volume in the rostral-medial striatum at all ages, and in cerebral cortex in HET mice at 6 and 10M. A bigger relative local volume in the cerebellum was observed at all ages in HET mice, and in the globus pallidus, substantia nigra, at 6 and 10M. Overall, this study revealed key structural abnormalities that resemble the natural history of PwHD. Hence, analysis of brain structure through MRI in the zQ175DN heterozygous mouse model holds potential for testing disease-modifying treatments expected to slow down or prevent structural degeneration. HighlightsO_LIThe striatum of zQ175DN heterozygous mice shows volume decrease at 3 months compared to WT mice C_LIO_LIWidespread volume reductions are observed from 6 months in zQ175DN heterozygous mice C_LIO_LITensor Based Morphometry highlights vulnerability of the dorsomedial striatum in the zQ175DN heterozygous mouse model C_LI

neuroscience↗

bioRxiv2023

Season-dependent processing of innate conspecific vocalizations in the male and female European starling (Sturnus vulgaris)

Avian innate nestling begging calls are similar to human infant cries in the behavioral response they elicit. However, it remains unknown whether the auditory processing of innate begging calls changes in seasonal songbirds from non-breeding to breeding season when hormonal neuromodulation of the auditory forebrain occurs. An fMRI experiment was set up to expose male and female European starlings (Sturnus vulgaris) to recordings of seasonal conspecific nestling begging calls in the breeding and non-breeding season. This response was compared with their response to conspecific warble motifs and artificial pure tones, both proven seasonally invariable at least in the male starlings neural response. Our results demonstrate significant seasonal variation in auditory forebrain responses exclusively elicited by begging calls and not by the applied control stimuli. Right Field L and the Caudomedial Nidopallium (NCM) seemed, irrespective of season or sex, more sensitive in response to begging than to control stimuli. A seasonal differential response specifically to begging calls was found in both sexes in a ventral midsagittal region of NCM. Our findings thereby support the functional fine-tuning of vocal communications between sender and receiver in a breeding context for innate vocalizations and are in line with the bi-parenting behavior in this species.

neuroscience↗