L. gasseri strain may support cognitive function in aged mice: Study

03-Feb-2023 - Last updated on 03-Feb-2023 at 16:36 GMT

The study adds to an ever-growing body of science supporting the microbiota-gut-brain axis. Image © inkoly / Getty Images

Supplementation with Lactobacillus gasseri NK109 may reduce cognitive impairment in aged mice, while also boosting expression of BDNF, says a new study.

BDNF (brain-derived neurotrophic factor) is a protein active in the brain and central and peripheral nervous systems that plays a key role in neuron development and repair and in protecting against neuro-degeneration.

Scientists from Kyung Hee University in Korea report that NK109 was also associated with decreases in levels of pro-inflammatory compounds in the brain and the colon of the lab animals.

Microbiota-gut-brain axis

The study adds to an ever-growing body of science supporting the microbiota-gut-brain axis is a bi-directional interaction between the gastrointestinal tract and the nervous system.

The researchers used three types of mice: Aged mice; 5XFAD transgenic mice (an engineered mouse that models major features of Alzheimer's Disease amyloid pathology); or adult mice given a fecal microbiota transplant from people with mild cognitive impairment (MCI). Each group of mice was further divided into three groups and given no supplement, the NK109 probiotic, or a supplement containing NK109 plus a soybean embryo ethanol extract (designated NS).

The data showed that the mice given the MCI fecal microbiota transplant did indeed result in behaviors indicative of cognitive impairment and induced neuroinflammation and colitis in the animals. When supplemented with the NK109 or NS, the cognitive impairment-like behaviors were reduced. NK109 or NS also reduced cognitive impairment-like behaviors in the 5XFAD transgenic mice.

Increases in the expression of BDNF in the hippocampus, were also reported for the supplemented animals, while levels of inflammatory TNF-alpha were decreased.

“[Fecal microbial transplantation] from patients with MCI caused cognitive impairment and neuroinflammation in mice, resulting in a useful MCI animal model,” said the researchers. “NK109 and its supplement NS may improve cognitive decline, neuroinflammation, and gut inflammation by modulating BDNF expression and gut microbiota.

“Gut microbiota dysbiosis-alleviating probiotics may be beneficial for the therapy of CI and systemic inflammation,” the concluded.

Source: Nutrients
2023, 15(3), 790; doi: 10.3390/nu15030790
“Lactobacillus gasseri NK109 and Its Supplement Alleviate Cognitive Impairment in Mice by Modulating NF-κB Activation, BDNF Expression, and Gut Microbiota Composition”
Authors: S-W. Yun et al.