Low-intensity pulsed ultrasound reduces oxidative and endoplasmic reticulum stress in motor neuron cells
Thi-Thuyet Truong, Chih-Chung Huang, Wen-Tai Chiu
Ultrasonics 2025, 146, 107499 · 10.1016/j.ultras.2024.107499
Abstract
Endoplasmic reticulum (ER) stress is associated with oxidative stress, which is integral to the development of various pathological conditions, including neurodegenerative disorders. In this study, using NSC-34-a hybrid cell line established by fusing motor neuron-rich embryonic spinal cord cells with mouse neuroblastoma cells-we investigated the effects of low-intensity pulsed ultrasound (LIPUS) stimulation on oxidative (reactive oxygen species)/ER stress-induced neurodegeneration. An ultrasound transducer with a center frequency of 1.15 MHz and a spatial peak temporal average intensity of 357 mW/cm 2 was used for delivering ultrasound (for 8 min, via a water-filled tube) to motor neuron cells seeded in a plastic culture dish. LIPUS stimulation significantly increased the level of the antiapoptotic protein B-cell lymphoma 2 (BCL-2) and inhibited the expression of apoptosis-associated proteins such as BCL-2-associated X protein (BAX), CCAAT/enhancer-binding protein-homologous protein (CHOP), and caspase-12, thus extending the survival of motor neurons. LIPUS stimulation also enhanced Ca 2+ signaling and activated the Ca 2+ -dependent transcription factors as nuclear factor of activated T cells (NFAT) and nuclear factor kappa-light-chain-enhancer of activated B cells (NF-κB). Furthermore, LIPUS stimulation induced the activation of the serine/threonine kinase protein kinase B (AKT). Thus, LIPUS stimulation prevented oxidative/ER stress-mediated mitochondrial dysfunction. In conclusion, as a safe and noninvasive method, LIPUS stimulation can facilitate further development of ultrasound neuromodulation as a tool for neuroscience research.
Abstract via europepmc.
Exposures
Exposure 1: LIPUS stimulation of NSC-34 motor neuron-like cells
Target: cultured neurons — “NSC-34 motor neuron-like hybrid cell line (motor neuron/spinal cord-derived)”
Device: Olympus / Panametrics · Olympus · A314S ✓
| Waveform | pulsed | |
|---|---|---|
| Fundamental frequency (kHz) | 1,150 | ✓✓✓ |
| Pulse duration (ms) | not reported | |
| Pulse repetition frequency (Hz) | 1,000 | ✓✓✓ |
| Duty cycle (%) | not reported | ⚑ |
| Sonication duration (s) | 480 | ✓✓✓ |
| Free-field pressure (kPa) | not reported | |
|---|---|---|
| Free-field Isppa (W/cm²) | not reported | |
| Free-field Ispta (W/cm²) | 0.357 | ✓✓✓ |
| In-situ estimate | not applicable | |
| In-situ pressure (kPa) | not applicable | |
| In-situ Isppa (W/cm²) | not applicable | |
| In-situ Ispta (W/cm²) | not applicable |
NSC-34 cells were subjected to LIPUS stimulation at a center frequency of 1.15 MHz, with a FWHM of 17.5 mm, a focal length of 80 mm, a spatial peak average temporal average intensity of 356.78 mW/cm2, and a pulse repetition frequency of 1 kHz for 8 min through a water-containing acrylic tube. Cells were stimulated on days 1 and 3, with cytotoxic challenge (thapsigargin, H2O2, or tunicamycin) applied for 6 h on day 3.
Flags from extraction
n_subjects— Paper reports statistics as 'at least three independent measurements' but does not state the number of independent cell cultures/dishes exposed to LIPUS.exposures[0].free_field— Hydrophone measurement was made in water in front of the transducer; cells were exposed via a water-filled tube through a thin culture medium layer with no skull or tissue path, so the free_field vs in_situ distinction is not explicitly stated by the paper.exposures[0].timing.duty_cycle_pct— Paper does not state duty cycle or pulse duration for this LIPUS protocol, only PRF (1 kHz) and total duration (8 min).target— NSC-34 is an immortalized motor-neuron-like hybrid cell line, not primary cultured neurons; closest vocabulary match (cultured_neurons) is imperfect.