N-acetylcysteine (NAC) ameliorates ethanol-induced oxidative stress, neuroinflammation, and cognitive dysfunction in APP/PS1 mouse model

Alzheimer's disease (AD) is the most prevalent neurodegenerative disorder that predominantly affects the elderly, leading to a progressive decline in cognitive function. Accumulating evidence suggests that many environmental and dietary factors, especially chronic ethanol exposure, aggravate the risk of this disease. However, its precise influence on AD has not yet been clarified. Here, we show that ethanol exposure caused earlier and severer cognitive behavioral impairments, more beta amyloid (Aβ) depositions, microglia activation, decreased total antioxidant capacity (T-AOC). Moreover, inflammatory mediators, such as Nucleotide-binding oligomerization domain-like receptor protein 3 (NLRP3) and Tumor necrosis factor-alpha (TNF-α) increased, while pivotal proteins involved in dendritic and synaptic development, such as Synaptophysin (SYP), postsynaptic density protein 95 (PSD95) and brain-derived neurotrophic factor (BDNF) decreased in APP/PS1 mice. N-acetylcysteine (NAC), a well-known antioxidant, could attenuate cognitive behavioral impairments and neuroinflammatory damage by restoring inflammatory and neurodevelopmental mediators. In general, our study uncovered that chronic ethanol exposure may exacerbate AD progress at the pathological and molecular levels and NAC may act as a potential drug for the treatment of AD patients with chronic ethanol exposure.