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ORIGINAL RESEARCH article

Front. Nutr.
Sec. Nutrition and Microbes
Volume 11 - 2024 | doi: 10.3389/fnut.2024.1439094
This article is part of the Research Topic Effects of Probiotics, Prebiotics, and Postbiotics on Microbiota-Gut-Brain Axis View all articles

Lactococcus strains with psychobiotic properties improve cognitive and mood alterations in aged mice

Provisionally accepted
Kan Gao Kan Gao 1*Cailing Chen Cailing Chen 2Zhiyao Zheng Zhiyao Zheng 2Qiuling Fan Qiuling Fan 2Haifeng Wang Haifeng Wang 1Yanjun Li Yanjun Li 2Su Chen Su Chen 2
  • 1 Zhejiang University, Hangzhou, China
  • 2 Hangzhou Wahaha Group Co., Ltd, Hangzhou, Jiangsu Province, China

The final, formatted version of the article will be published soon.

    Aging often accompanies cognitive and mood disturbances. Emerging evidence indicates that specific probiotics mitigate cognitive and mood dysfunctions. Strains within Lactococcus, a subgroup of probiotics, including L. lactis and L. cremoris are shown beneficial effects on brain functions via the gut microbiota-brain axis (GBA). Our previous study identified two Lactococcus strains (L. lactis WHH2078 and L. cremoris WHH2080) with the ability to promote the secretion of gut 5-hydroxytryptophan (5-HTP), the precursor of the GBA mediator 5-hydroxytryptamine (5-HT).In this study, the modulatory effects of WHH2078 and WHH2080 on cognitive and mood alternations were investigated in aged mice. Oral administration of WHH2078 and WHH2080 (1×10 9 CFU/mL/day) in aged mice (12-month-old) for 12 weeks significantly improved cognitive and depressive-and anxiety-like behaviors. The neuronal loss, the 5-HT metabolism dysfunction, and the neuroinflammation in the hippocampus of aged mice were restored by WHH2078 and WHH2080. the disturbances in the serum tryptophan metabolism in aged mice were unveiled by metabolomics, notably with decreased levels of 5-HT and 5-HTP, and increased levels of kynurenine, 3-hydroxykynurenine, and indolelactic acid, which were reversed by WHH2078 and WHH2080.Regarding the gut microbial community, WHH2078 and WHH2080 restored the increased abundance of Firmicutes, Desulfobacterota, and Deferribacterota and the decreased abundance of Bacteroidota and Actinobacteriota in aged mice. The beneficial effects of the two strains were linked to the modulation of 5-HT metabolism and gut microbiota. Our findings point to the potential role of Lactococcus strains with 5-HTP-promoting abilities as therapeutic approaches for agerelated cognitive and mood disorders.

    Keywords: Lactoccous, gut microbiota-brain axis, Cognition, mood, 5-HT

    Received: 27 May 2024; Accepted: 23 Jul 2024.

    Copyright: © 2024 Gao, Chen, Zheng, Fan, Wang, Li and Chen. This is an open-access article distributed under the terms of the Creative Commons Attribution License (CC BY). The use, distribution or reproduction in other forums is permitted, provided the original author(s) or licensor are credited and that the original publication in this journal is cited, in accordance with accepted academic practice. No use, distribution or reproduction is permitted which does not comply with these terms.

    * Correspondence: Kan Gao, Zhejiang University, Hangzhou, China

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