Science China Life Sciences

, Volume 59, Issue 10, pp 1006–1023 | Cite as

Alzheimer’s disease and gut microbiota

  • Xu Hu
  • Tao Wang
  • Feng JinEmail author
Open Access


Alzheimer’s disease (AD) is a most common neurodegenerative disorder, which associates with impaired cognition. Gut microbiota can modulate host brain function and behavior via microbiota-gut-brain axis, including cognitive behavior. Germ-free animals, antibiotics, probiotics intervention and diet can induce alterations of gut microbiota and gut physiology and also host cognitive behavior, increasing or decreasing risks of AD. The increased permeability of intestine and blood-brain barrier induced by gut microbiota disturbance will increase the incidence of neurodegeneration disorders. Gut microbial metabolites and their effects on host neurochemical changes may increase or decrease the risk of AD. Pathogenic microbes infection will also increase the risk of AD, and meanwhile, the onset of AD support the “hygiene hypothesis”. All the results suggest that AD may begin in the gut, and is closely related to the imbalance of gut microbiota. Modulation of gut microbiota through personalized diet or beneficial microbiota intervention will probably become a new treatment for AD.


Alzheimer’s disease gut microbiota leaky gut leaky brain diet infection hygiene hypothesis 


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© The Author(s) 2016

Authors and Affiliations

  1. 1.Key Laboratory of Mental Health, Institute of PsychologyChinese Academy of SciencesBeijingChina

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