Development of effective inhibitors toward A beta aggregation and reactive oxygen species (ROS) scavengers are of crucial therapeutic implications for Alzheimer's disease (AD). Herein, a novel agent with dual enzyme mimic activities has been fabricated as a multifunctional A beta fibrillation modulator. MoO3-x nanodots were synthesized by pulsed laser ablation (PLA) method in MoS2 nanosheets solutions, which may act directly as numerous fine targets. MoO3-x nanodots showed a uniform and monodispersed morphology, and the tiny dots were around 3-5 nm with a narrow size distribution. Due to the efficient charge transition between Mo5+/Mo6+ on the dots surface, MoO3-x nanodots exhibited excellent catalase and SOD mimic activities, which were adopted to alleviate A beta-mediated oxidative stress. Moreover, MoO3-x nanodots can efficiently inhibit A beta aggregation and destabilize the preformed fibrils, and eventually protect neuronal cells from apoptosis induced by A beta. Taken together, MoO3-x nanodots with multifunctional roles can act as a potential therapeutic strategy for treatment of amyloid induced neurotoxicity. (C) 2019 Elsevier Inc. All rights reserved.