Transcranial Ultrasound Improves Behavioral Performance via Anti-Neuroinflammation

The purpose of this study was to investigate the protective role of low-intensity pulsed ultrasound (LIPUS) against lipopolysaccharide (LPS)-induced neuroinflammation and memory impairments in a mouse model. A 1.0 MHz focused ultrasound transducer was exploited to sonicate the brain noninvasively with 50 ms burst lengths at a 5% duty cycle, a repetition frequency of 1 Hz. Mice subjected to LPS administration (250 μg/kg, i.p.) were treated with LIPUS daily for 7 days. The levels of inflammatory markers were estimated in brain tissue using western blot. After LIPUS treatment, the neuroprotective effects of LIPUS in mice were assessed by behavioral analysis using the Morris water maze. The average escape latencies were significantly shortened in LPS plus LIPUS-treated mice from the sixth day of the acquisition phase. Furthermore, LIPUS significantly reduced the protein levels of TNF-α, IL-1β, and IL-6 in the mice brain induced by LPS. LIPUS treatment shows neuroprotection by inhibiting LPS-induced activation of TLR4 inflammatory signaling. Our data showed that LIPUS attenuated LPS-induced memory impairment via suppression of neuroinflammatory activity.