functional ultrasound device  (ICONEUS)

Journal: bioRxiv

Article Title: Rejuvenation of the Aged Cerebrovascular System via Protein Corona–Guided Fusogenic Liposome Delivery

doi: 10.64898/2026.03.05.709925

Figure Lengend Snippet: A) Representative images of the cerebral microvasculature recorded by functional ultrasound imaging resulting in the presented ultrasound localization microscopy images. Vascular density has been measured in the cortical (CX) and hippocampal (HIPP) areas of the mouse brain. B–C) Quantification of the cortical and hippocampal cerebral vascular density in young, aged, aged + FL-RSV and aged + ApoE-FL-RSV treated animals. D–E) Measurement of neurovascular coupling responses in the young, aged, aged + FL-RSV and aged + ApoE-FL-RSV treated mice. Note the significant differences between aged, aged + FL-RSV and aged + ApoE-FL-RSV. Data is shown in mean±SEM. *p<0.05, **p<0.01, ***p<0.001 with ANOVA, N≥8 for all groups. F) Single-cell RNA-seq analysis reveals restoration of endothelial heterogeneity with treatment. Stacked bar plots showing the proportional abundance of vascular cell populations across experimental groups. Aging markedly reduces angiogenic and proliferating endothelial subtypes, whereas FL-RSV and particularly APOE-FL-RSV treatment partially restores endothelial diversity and the presence of regenerative cell states, suggesting improved vascular maintenance capacity. G) Gene ontology enrichment indicates reduced endothelial senescence and improved barrier maintenance after APOE-FL-RSV treatment. Heatmap of endothelial GO term enrichment scores demonstrates that aging increased pathways associated with cellular senescence, endothelial stress, and barrier dysfunction, while APOE-FL-RSV shifted expression toward gene sets linked to blood–brain barrier integrity, lipid transport, and endothelial homeostasis. H-I) Measurement of learning and memory functions of the young, aged, aged + FL-RSV, aged + ApoE-FL-RSV treated animals and aged animals that have RSV per os . Young control and aged BL6 mice were subjected to vehicle, RSV per os , FL-RSV and ApoE-FL-RSV treatments and assessed for their spatial learning and memory using the Radial Arm Water Maze (RAWM). During the learning phase (days 2 to 6) and on probe (P), retrieval (R) and relearn (L) days aged mice displayed higher combined error rates compared to young mice. Treatment with FL-RSV and ApoE-FL-RSV significantly enhanced learning performance in aged mice relative to their untreated counterparts. The combined error rate was computed by adding one error for each incorrect arm entry plus an error for every 15 seconds of inactivity. Data are presented as mean±SEM (N=10–15 per group). Statistical significance indicated by *p<0.05, **p<0.01, ***p<0.001 using Repeated Measure ANOVA, demonstrating the beneficial effects of FL-RSV and ApoE-FL-RSV treatments on enhancing cognitive functions in aged mice, particularly in spatial learning, but less so in tasks requiring cognitive flexibility.

Article Snippet: The ultrasonic probe (IcoPrime-4D MultiArray 15 MHz, ICONEUS, France) of the ICONEUS One functional ultrasound device (ICONEUS, France) was positioned directly above the cranial window and submerged in ultrasound gel (Gel de contact, Drexco Medical, France).

Techniques: Functional Assay, Imaging, Ultrasound Localization Microscopy, Single Cell, RNA Sequencing, Expressing, Control