Effects of Low-Intensity Transcranial Pulsed Ultrasound Treatment in a Model of Alzheimer's Disease
Natalia dos Santos Tramontin, Paulo Cesar Lock Silveira, Lariani Tamires Witt Tietbohl, Bárbara Da Costa Pereira, Kellen Simon, Alexandre Pastoris Muller
Ultrasound in Medicine & Biology 2021 · 10.1016/j.ultrasmedbio.2021.05.007
Abstract
Alzheimer's disease (AD) is the most common neurodegenerative disease. One of the main pathology markers of AD is the beta-amyloid plaques (βA 1-42 ) created from residues of the badly processed amyloid precursor protein. The accumulation of these plaques can induce neuroinflammation and oxidative stress and impair antioxidant mechanisms, culminating in cognitive and memory deficits. New therapies are necessary to treat AD as the approved drugs do not treat the progress of the disease. Transcranial low-intensity pulsed ultrasound (LIPUS) affects brain metabolism and could be tested as a treatment for AD. This study was aimed at evaluating the LIPUS treatment in a model of AD induced by βA 1-42 intracerebroventricularly (ICV) and its effects on learning memory, neurotrophins, neuroinflammation and oxidative status. βA 1-42 was administered ICV 24 h before the start of a 5-wk LIPUS treatment. The treatment with LIPUS improved recognition memory, as well as increasing nerve growth factor β and brain-derived neurotrophic factor levels in the hippocampus and cortex. There was a decrease in protein damage in the hippocampus treated with LIPUS. Neuroinflammation and oxidative stress were not present in the AD model used. The results indicated that LIPUS is a novel and promising adjuvant strategy for treatment of the late stage of AD.
Abstract via europepmc.
Exposures
Exposure 1: beta-amyloid + LIPUS group
Target: brain — “transcranially”
Device: other named manufacturer · Ibramed
| Waveform | pulsed | |
|---|---|---|
| Fundamental frequency (kHz) | 3,300 | ✓✓✓⚑ |
| Pulse duration (ms) | 5 | ✓✓✓ |
| Pulse repetition frequency (Hz) | 100 | ✓✓✓ |
| Duty cycle (%) | 50pulse duration × PRF gives 50% | ✓✓✓ |
| Sonication duration (s) | not reported |
| Free-field pressure (kPa) | not reported | |
|---|---|---|
| Free-field Isppa (W/cm²) | not reported | |
| Free-field Ispta (W/cm²) | not reported | |
| In-situ estimate | not reported | |
| In-situ pressure (kPa) | not reported | |
| In-situ Isppa (W/cm²) | not reported | |
| In-situ Ispta (W/cm²) | not reported | |
| Ispta, domain unspecified (W/cm²) | 0.8 | ✓?⚑ |
Treatment began 24 h after the beta-amyloid infusion and was given at 48-h intervals for 5 weeks (35 d), transcranially with conductive gel under isoflurane; sonication time per session is not stated.
Flags from extraction
exposures[0].unspecified_domain.ispta_w_cm2— Intensity of 0.8 W/cm2 is given without type or domain; placed as ispta in unspecified_domain on the assumption of a physiotherapy-device spatial-average temporal-average specification, which the paper does not say.exposures[0].fundamental_frequency_khz— Central frequency 3.3 MHz +/- 10 percent from a commercial physiotherapy-type device (Ibramed); the field is a transcranial exposure of the whole head with a 7.0 cm2 effective radiating area, so the target is recorded as brain.exposures[0].device.manufacturer— Manufacturer inferred from the citation '(Ibramed 2012)' after the parameter list; no model is named.n_subjects— N = 23 rats overall in groups of 8, 9 and 6; figure legends report n = 9, 6 and 8 inconsistently. Recorded the LIPUS group size of 6.blinding— Not stated.