Effect of low-frequency but high-intensity noise exposure on swine brain blood barrier permeability and its mechanism of injury

Objectives: Vibroacousitic disease (VAD) is caused by excessive exposure to low-frequency but high-intensity noise. The integrity of the brain blood barrier (BBB) is essential for the brain. The study aimed to investigate the effect of noise exposure on the BBB. Methods: Healthy male Bama swine were exposed to 50, 70, 100, and 120 Hz, 140 dB noise for 30 min. After exposure, CT brain imaging and ex vivo fluorescent imaging of parenchymal EB leakage were performed (each group consisted of N = 3 swine). The human cerebral microvascular endothelial cells were exposed to 70 Hz, 140 dB noise for 5 min. Results: The BBB permeability assay showed that 50, 70, and 100 Hz with 140 dB noise exposure accelerated BBB permeability, and the BBB opening at 70 Hz was most serious and reversible. Additionally, CT images demonstrated that the noise-induced opening of the BBB caused no intracerebral hemorrhage. This noise-induced BBB opening was related to the downregulation of zo-1 and occludin. Finally, cysteinyl leukotriene receptor 1 (CysLT1 receptor) was found to regulate noise-induced tight junction defects in vitro. Conclusions: In conclusion, noise exposure accelerates the formation of a high-permeability BBB with leaky tight junctions through a CysLT1-mediated mechanism, which warrants additional research.