Around-the-Clock Noise Induces AD-like Neuropathology by Disrupting Autophagy Flux Homeostasis

• Published in: Cells (Basel, Switzerland) Vol. 11; no. 17; p. 2742
• Main Authors: Zheng, Pengfang, She, Xiaojun, Wang, Chunping, Zhu, Yingwen, Fu, Bo, Ma, Kefeng, Yang, Honglian, Gao, Xiujie, Li, Xiaofang, Wu, Fangshan, Cui, Bo
• Format: Journal Article
• Language: English
• Published: Basel MDPI AG 01.09.2022; MDPI
• Subjects: Alzheimer's disease; AMPK-mTOR; Animal cognition; Antibodies; Apoptosis; around-the-clock noise; autophagosome; Autophagy; Autophagy (Cytology); Biotechnology; Central nervous system; Cognitive ability; Cortex; Development and progression; Gene expression; Health aspects; Hippocampus; Homeostasis; Inflammation; Kinases; Laboratory animals; lysosome; Nervous system diseases; Neurodegenerative diseases; Neuropathology; Noise; Phosphorylation; Proteins; Signal transduction; Statistical analysis; Tau protein; TOR protein; Transmission electron microscopy; β-Amyloid; China; Beijing China; United Kingdom > UK; United States > US
• ISSN: 2073-4409; 2073-4409
• DOI: 10.3390/cells11172742

Environmental noise is a common hazard in military operations. Military service members during long operations are often exposed to around-the-clock noise and suffer massive emotional and cognitive dysfunction related to an Alzheimer’s disease (AD)-like neuropathology. It is essential to clarify the mechanisms underlying the effects of around-the-clock noise exposure on the central nervous system. Here, Wistar rats were continuously exposed to white noise (95 dB during the on-duty phase [8:00–16:00] and 75 dB during the off-duty phase (16:00–8:00 the next day)) for 40 days. The levels of phosphorylated tau, amyloid-β (Aβ), and neuroinflammation in the cortex and hippocampus were assessed and autophagosome (AP) aggregation was observed by transmission electron microscopy. Dyshomeostasis of autophagic flux resulting from around-the-clock noise exposure was assessed at different stages to investigate the potential pathological mechanisms. Around-the-clock noise significantly increased Aβ peptide, tau phosphorylation at Ser396 and Ser404, and neuroinflammation. Moreover, the AMPK-mTOR signaling pathway was depressed in the cortex and the hippocampus of rats exposed to around-the-clock noise. Consequently, autophagosome–lysosome fusion was deterred and resulted in AP accumulation. Our results indicate that around-the-clock noise exposure has detrimental influences on autophagic flux homeostasis and may be associated with AD-like neuropathology in the cortex and the hippocampus.