Effect of Fluoxetine and Acacetin on Central Vestibular Compensation in an Animal Model of Unilateral Peripheral Vestibulopathy

Development of NIR photocleavable nanoparticles with BDNF for vestibular neuron regeneration

Among nanoparticle platforms, light or photoresponsive nanoparticles have emerged as a promising drug delivery strategy with spatiotemporal control while minimizing off-target effects. The characteristic absorption spectrum of the photoresponsive moiety dictates the wavelength of light needed to activate bond cleavage. However, the low tissue penetration depth limit and short-wavelength ultraviolet (UV) cellular toxicity are considered disadvantageous. This study developed a vestibular ganglion neuron organoid as a model for vestibulopathy. UV and near-infrared (NIR) radiation targeted the inner ear and neural cells, followed by toxicity evaluation. A significantly smaller toxicity of NIR light was confirmed. The photocleavage release of brain-derived neurotrophic factor (BDNF) was used by applying NIR wavelength. The results indicate that polyethylene glycol octamethylene diamine derivative conjugated with leucomethylene blue with an ethanolamine linker nanoparticle can be effectively disassembled and release BDNF when using the 808 nm laser as a trigger. The findings of the cytotoxicity assay suggest that photocleavable nanoparticles (PCNs) and laser irradiation are safe and biocompatible for human-derived and neural progenitor types of cells. Phototriggered BDNF release by NIR laser supported the growth and differentiation of human neural progenitor cells in culture. In addition, the vestibulopathy organoid exhibited a significant regenerative effect. This study harnesses the full potential of NIR laser PCNs to treat vestibular neuropathies.

Animal Models of Neurological Disorders: Where Are We Now?

The Special Issue "Animal Models of Neurological Disorders: Where Are We Now [...].

Vertigoheel improves central vestibular compensation after unilateral peripheral vestibulopathy in rats

The aim of this study was to assess the effect of Vertigoheel on central vestibular compensation and cognitive deficits in rats subjected to peripheral vestibular loss. Young adult male Long Evans rats were subjected to bilateral vestibular insults through irreversible sequential ototoxic destructions of the vestibular sensory organs. Vestibular syndrome characteristics were monitored at several time points over days and weeks following the sequential insults, using a combination of behavioral assessment paradigms allowing appreciation of patterns of change in static and dynamic deficits, together with spatial navigation, learning, and memory processes. Vertigoheel administered intraperitoneally significantly improved maximum body velocity and not moving time relative to its vehicle control on days 2 and 3 and on day 2, respectively, after unilateral vestibular lesion (UVL). It also significantly improved postural control relative to its vehicle 1 day after UVL. Conversely, Vertigoheel did not display any significant effect vs. vehicle on the severity of the syndrome, nor on the time course of other examined parameters, such as distance moved, mean body velocity, meander, and rearing. Spatial cognition testing using Y- and T-maze and eight-radial arm maze did not show any statistically significant difference between Vertigoheel and vehicle groups. However, Vertigoheel potentially enhanced the speed of learning in sham animals. Evaluating Vertigoheel's effect on thigmotaxis during the open-field video tracking test revealed no significant difference between Vertigoheel and its vehicle control groups suggesting that Vertigoheel does not seem to induce sedative or anxiolytic effects that could negatively affect vestibular and memory function. Present observations reveal that Vertigoheel improves central vestibular compensation following the unilateral peripheral vestibular loss as demonstrated by improvement of specific symptoms.