Long-term effects of acute hazardous noise on auditory and non-auditory organs.

Abstract

Hazardous noise is a pervasive environmental pollutant with significant adverse health impacts on auditory and non-auditory organs. It is noteworthy that even acute noise exposure might pose immediate detrimental effects to various organs. However, the long-term effects of acute noise exposure remain largely unknown. This study aimed to explore this gap by randomizing 12 Long-Evans rats into acute noise and control groups. The acute noise regimen was a single three-hr wideband noise (12.5 hz-20 kHz) at 105 dB SPL_peak. Four weeks following exposure cessation, animals from both groups were sacrificed. Genomic DNA and RNA were extracted from the cochlea, brain, heart, and liver. Long-target polymerase assays and real-time quantitative polymerase chain reactions were performed to assess DNA integrity and p53-targeted gene expression, respectively, with results being compared between the two groups. Data demonstrated that noise-induced changes in DNA integrity depended upon organ type, with significant interaction effects between treatment conditions (noise or control) and organ type for nuclear and mitochondrial DNA integrity. In addition, there were significant changes in p53-targeted gene expression between noise-exposed and control in all tested organs. In conclusion, the long-term impact of acute hazardous noise exposure on DNA integrity was complex, highlighting organ-specificity in response to noise. However, such noise significantly altered p53-targeted genes systemically, indicating ongoing cellular stress. Overall, these results suggest that acute exposure to hazardous noise may have potential long-term adverse consequences. Immediate care following exposure might mitigate possible impacts on long-term health.