Effect of N-Acetyl Cysteine as an Adjuvant Treatment in Alzheimer's Disease

Oxidative stress levels are exacerbated in Alzheimer's disease (AD). This phenomenon feeds back into the overactivation of oxidase enzymes, mitochondrial dysfunction, and the formation of advanced glycation end-products (AGEs), with the stimulation of their receptors (RAGE). These factors stimulate Aβ peptide aggregation and tau hyperphosphorylation through multiple pathways, which are addressed in this paper. The aim of this study was to evaluate the regulatory effect of N-acetyl cysteine (NAC) on oxidant/antioxidant balance as an adjuvant treatment in patients with AD. The results obtained showed that NAC supplementation produced improved cognitive performance, decreased levels of oxidative stress markers, lowered activities of oxidase enzymes, increased antioxidant responses, and attenuated inflammatory and apoptotic markers. Moreover, NAC reversed mitochondrial dysfunction, lowered AGEs-RAGE formation, attenuated Aβ peptide oligomerization, and reduced phosphorylation of tau, thereby halting the formation of neurofibrillary tangles and the progression of AD.