Related Experiment Video

Updated: Jul 8, 2026

A High-performance Liquid Chromatography Measurement of Kynurenine and Kynurenic Acid: Relating Biochemistry to Cognition and Sleep in Rats
07:04

A High-performance Liquid Chromatography Measurement of Kynurenine and Kynurenic Acid: Relating Biochemistry to Cognition and Sleep in Rats

Published on: August 19, 2018

Exploring the Microbiome-Kynurenine Axis in Mild Cognitive Impairment: From Gut to Brain

Jiaxing Zhu1, Haihua Xie1, Yingke Ouyang1

  • 1College of Acupuncture & Tuina and Rehabilitation, Hunan University of Chinese Medicine, 410208 Changsha, Hunan, China.

Journal of Integrative Neuroscience
|July 7, 2026
PubMed

Insights

Gut microbiota changes trigger inflammation and alter brain metabolism, driving mild cognitive impairment (MCI) progression. Targeting this gut-immune-metabolic cycle may delay dementia.

Area of Science:

  • Neuroscience
  • Microbiology
  • Immunology

Background:

  • Mild cognitive impairment (MCI) is a precursor to Alzheimer's disease.
  • Gut microbiota dysbiosis is implicated in various neurological disorders.

Purpose of the Study:

  • To review the pathological cascade linking gut dysbiosis to MCI.
  • To propose therapeutic targets within the gut-immune-metabolic axis.

Main Methods:

  • Literature review synthesizing evidence on MCI pathogenesis.
  • Analysis of the role of gut microbiota, inflammation, and tryptophan metabolism.

Main Results:

  • Gut dysbiosis (e.g., altered Prevotella and Akkermansia) leads to butyrate deficit and compromised gut integrity.
  • Systemic inflammation upregulates IDO1, favoring neurotoxic kynurenine pathway metabolites.
  • This imbalance promotes excitotoxicity, oxidative stress, and neuroinflammation, causing cognitive decline.

Conclusions:

  • A 'gut-immune-metabolic' vicious cycle drives MCI progression.
  • Dual therapeutic strategies targeting microbial restoration and IDO1/KMO inhibition show promise for delaying dementia.
Keywords:
gut microbiotagut-brain axiskynureninemild cognitive impairmentreview

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