← Explore

Low-intensity pulsed ultrasound modulates disease progression in the SOD1G93A mouse model of amyotrophic lateral sclerosis

Zihao Liu, Huan Zhang, Kaili Lu, Li Chen, Yueqi Zhang, Zhouwei Xu, Hongsheng Zhou, Junfeng Sun, Mengyang Xu, Qi Ouyang, Garth J. Thompson, Yi Yang, Ni Su, Xiaojun Cai, Li Cao, Yuwu Zhao, Lixian Jiang, Yuanyi Zheng, Xiaojie Zhang

Cell Reports 2024, 43, 114660 · 10.1016/j.celrep.2024.114660

rodentin vitro cellotherbehaviourother mricellular imaginghistology molecular

Abstract

Amyotrophic lateral sclerosis (ALS) is a devastating neurodegenerative disease characterized by the progressive loss of motor neurons in the brain and spinal cord, and there are no effective drug treatments. Low-intensity pulsed ultrasound (LIPUS) has garnered attention as a promising noninvasive neuromodulation method. In this study, we investigate its effects on the motor cortex and underlying mechanisms using the SOD1 G93A mouse model of ALS. Our results show that LIPUS treatment delays disease onset and prolongs lifespan in ALS mice. LIPUS significantly increases cerebral blood flow in the motor cortex by preserving vascular endothelial cell integrity and increasing microvascular density, which may be mediated via the ion channel TRPV4. RNA sequencing analysis reveals that LIPUS substantially reduces the expression of genes associated with neuroinflammation. These findings suggest that LIPUS applied to the motor cortex may represent a potentially effective therapeutic tool for the treatment of ALS.

Abstract via europepmc.

Speciesmouse (SOD1-G93A transgenic and wild-type littermates); mouse brain endothelial cell line (b.End.3), astrocyte cell line (C8-D1A)
Subjects31, 23swept animals
Sessions per subjectnot reported
Randomisedyes
Blindingsingle
Sham / controlno treatment control
Auditory controlnot reported
Readout timingoffline
Anaesthesiaanaesthetised
Readoutsbehaviour, other mri, cellular imaging, histology molecularRotarod disease-onset test; CatWalk gait analysis; hindlimb grip strength; pseudo-continuous arterial spin labelling (pCASL) MRI cerebral blood flow; in vivo multiphoton imaging of cortical capillaries; Nissl/H&E staining; immunohistochemistry (SMI-32, Iba1, GFAP, CD31); western blot; RNA-seq/qRT-PCR; TEER and FITC-dextran BBB permeability assays (in vitro)
Direction of effectmixed or unclearLIPUS to motor cortex delayed disease onset, prolonged lifespan and disease duration, improved gait and grip strength, increased cerebral blood flow and microvascular density, preserved endothelial cell/BBB integrity, reduced neuroinflammation (glial activation, TNF/NF-kB pathway genes) and mitochondrial damage, and increased motor neuron survival in SOD1-G93A mice; protective effects on endothelial cells were TRPV4-dependent in vitro.
Adverse eventsnone observedNo morphological changes were observed in the motor cortex by H&E staining at the frequency and intensity used, indicating LIPUS caused no brain injury; no obvious temperature elevation was observed during in vitro LIPUS intervention.

Exposures

Exposure 1: LIPUS to motor cortex in SOD1-G93A and wild-type mice

Target: motor cortex — “motor cortex
Device: other named manufacturer · Shanghai Acoustics Laboratory

Pulse timing
Waveformpulsed
Fundamental frequency (kHz)572✓✓
Pulse duration (ms)not reportedimplied by duty cycle ÷ PRF: 10 ms (not stated by the paper)
Pulse repetition frequency (Hz)50✓✓
Duty cycle (%)50✓✓
Sonication duration (s)1,800✓✓
Pressure and intensity, by domain
Free-field pressure (kPa)not reported
Free-field Isppa (W/cm²)0.82✓✓
Free-field Ispta (W/cm²)not reported
In-situ estimatenot reported
In-situ pressure (kPa)not reported
In-situ Isppa (W/cm²)not reported
In-situ Ispta (W/cm²)not reported
Protocol, in the paper’s words

LIPUS therapy was performed for 30 min every two days for each mouse, using a wearable transducer positioned via a stereotactic system over a point in front of Bregma; Inter-Stimulus-Interval (ISI) = 1 s.

Exposure 2: LIPUS applied to SOD1-G93A-overexpressing brain endothelial cells (b.End.3) in vitro

Target: other — “cultured mouse brain endothelial cell line (b.End.3)
Device: other named manufacturer · Shanghai Acoustics Laboratory

Pulse timing
Waveformpulsed
Fundamental frequency (kHz)572✓✓
Pulse duration (ms)not reportedimplied by duty cycle ÷ PRF: 10 ms (not stated by the paper)
Pulse repetition frequency (Hz)50✓✓
Duty cycle (%)50✓✓
Sonication duration (s)300✓✓
Pressure and intensity, by domain
Free-field pressure (kPa)not reported
Free-field Isppa (W/cm²)0.4✓✓
Free-field Ispta (W/cm²)not reported
In-situ estimatenot applicable
In-situ pressure (kPa)not applicable
In-situ Isppa (W/cm²)not applicable
In-situ Ispta (W/cm²)not applicable
Protocol, in the paper’s words

The same ultrasound device and centre frequency/PRF/duty-cycle/ISI as the in vivo experiments were used; each LIPUS intervention on b.End.3 cells lasted 5 min. Control cells were placed on the transducer for the same duration with the device turned off.

Flags from extraction

  • n_subjectsReported as two non-overlapping group sizes (Tg-US N=31 SOD1-G93A mice; WT-US N=23 wild-type littermates) that both received LIPUS; given as a list per group rather than summed.
  • n_sessions_per_subjectLIPUS was given 'every two days' from an unspecified start until variable disease-stage endpoints (mice were followed to onset/death, which varied by animal); no fixed total session count is stated.
  • exposures[0].timing.pulse_duration_msPRF (50 Hz) and duty cycle (50%) are stated but pulse duration is not given directly in the text; not computed from PRF/duty cycle per protocol.
  • exposures[1].timing.pulse_duration_msSame as exposures[0]: PRF and duty cycle stated, pulse duration not given directly.
  • sham_typeUntreated control mice (Tg-NT, WT-NT) were only anaesthetised with no transducer or sham device applied; mechanism not otherwise described.