This study aims to identify whether abdominal ultrasound stimulation can prevent cognitive decline in aging-accelerated mice (SAMP8) by evaluating cognitive performance, number of neurons, amyloid-β protein deposition, Tau protein hyperphosphorylation, neuroinflammation, and synaptic plasticity.
Six-month-old male SAMP8 mice were randomly assigned to either an aging group or an ultrasound stimulation group, with age-matched SAMR1 mice serving as healthy controls (n = 12). The abdominal ultrasound treatment was administered daily at 1 MHz and 1.0 W/cm² with a 20% duty cycle for 30 minutes over one month. Following the ultrasound intervention, a cognitive performance test was conducted using the Morris water maze, and brain tissues were collected for further analysis. Neuronal counts were quantified through Nissl staining, while amyloid-β deposition, Tau hyperphosphorylation, and neuroinflammatory markers (Iba1 and GFAP) were assessed via immunohistochemical staining. Synaptic plasticity was evaluated by analyzing PSD95 and synaptophysin levels through Western blotting. Statistical analysis was performed using one-way ANOVA followed by Tukey’s post-hoc test.
The aging group showed a significant decline in cognitive performance, although no significant improvement observed in the ultrasound group relative to the aging group. In the cortex, the ultrasound group showed a significant increase in neuronal cells compared to the aging group, whereas no significant changes were observed in the hippocampus. Additionally, amyloid-β deposition in the cortex was notably lower in the ultrasound group than in the aging group. In the hippocampus and cortex, the levels of Tau hyperphosphorylation and neuroinflammatory markers were significantly reduced in the ultrasound group compared to the aging group. Furthermore, PSD95 levels in the cortex showed a tendency toward increase in the ultrasound group (P = 0.058), and synaptophysin levels were significantly elevated in both the hippocampus and cortex.
Overall, abdominal ultrasound stimulation effectively reduced neuronal loss and amyloid-β accumulation in the cortex. Additionally, it alleviated Tau hyperphosphorylation and neuroinflammation, and improved synaptic plasticity, suggesting potential neuroprotective effects in aging mice.
This study raises the possibility that abdominal ultrasound stimulation offers a promising, non-invasive approach to reduce age-related cognitive decline and providing therapeutic options for older adults who cannot engage in sufficient physical activity.
Cognitive decline
Neuroplasticity
