1
|
Brandt A, Kromm F, Hernández-Arriaga A, Martínez Sánchez I, Bozkir HÖ, Staltner R, Baumann A, Camarinha-Silva A, Heijtz RD, Bergheim I. Cognitive Alterations in Old Mice Are Associated with Intestinal Barrier Dysfunction and Induced Toll-like Receptor 2 and 4 Signaling in Different Brain Regions. Cells 2023; 12:2153. [PMID: 37681885 PMCID: PMC10486476 DOI: 10.3390/cells12172153] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2023] [Revised: 08/24/2023] [Accepted: 08/25/2023] [Indexed: 09/09/2023] Open
Abstract
Emerging evidence implicate the 'microbiota-gut-brain axis' in cognitive aging and neuroinflammation; however, underlying mechanisms still remain to be elucidated. Here, we assessed if potential alterations in intestinal barrier function and microbiota composition as well as levels of two key pattern-recognition receptors namely Toll-like receptor (TLR) 2 and TLR4, in blood and different brain regions, and depending signaling cascades are paralleling aging associated alterations of cognition in healthy aging mice. Cognitive function was assessed in the Y-maze and intestinal and brain tissue and blood were collected in young (4 months old) and old (24 months old) male C57BL/6 mice to determine intestinal microbiota composition by Illumina amplicon sequencing, the concentration of TLR2 and TLR4 ligands in plasma and brain tissue as well as to determine markers of intestinal barrier function, senescence and TLR2 and TLR4 signaling. Cognitive function was significantly impaired in old mice. Also, in old mice, intestinal microbiota composition was significantly altered, while the relative abundance of Gram-negative or Gram-positive bacteria in the small and large intestines at different ages was not altered. Moreover, intestinal barrier function was impaired in small intestine of old mice, and the levels of TLR2 and TLR4 ligands were also significantly higher in both portal and peripheral blood. Furthermore, levels of TLR2 and TLR4 ligands, and downstream markers of TLR signaling were higher in the hippocampal and prefrontal cortex of old mice compared to young animals. Taken together, our results suggest that even in 'healthy' aging, cognitive function is impaired in mice going along with an increased intestinal translocation of TLR ligands and alterations of TLR signaling in several brain regions.
Collapse
Affiliation(s)
- Annette Brandt
- Department of Nutritional Sciences, Molecular Nutritional Science, University of Vienna, 1090 Vienna, Austria
| | - Franziska Kromm
- Department of Nutritional Sciences, Molecular Nutritional Science, University of Vienna, 1090 Vienna, Austria
| | - Angélica Hernández-Arriaga
- Animal Nutrition Department, Institute of Animal Science, University of Hohenheim, 70593 Stuttgart, Germany
| | - Inés Martínez Sánchez
- Department of Neuroscience, Karolinska Institute, Biomedicum, 17177 Stockholm, Sweden
| | - Haktan Övül Bozkir
- Department of Nutritional Sciences, Molecular Nutritional Science, University of Vienna, 1090 Vienna, Austria
| | - Raphaela Staltner
- Department of Nutritional Sciences, Molecular Nutritional Science, University of Vienna, 1090 Vienna, Austria
| | - Anja Baumann
- Department of Nutritional Sciences, Molecular Nutritional Science, University of Vienna, 1090 Vienna, Austria
| | - Amélia Camarinha-Silva
- Animal Nutrition Department, Institute of Animal Science, University of Hohenheim, 70593 Stuttgart, Germany
| | - Rochellys Diaz Heijtz
- Department of Neuroscience, Karolinska Institute, Biomedicum, 17177 Stockholm, Sweden
| | - Ina Bergheim
- Department of Nutritional Sciences, Molecular Nutritional Science, University of Vienna, 1090 Vienna, Austria
| |
Collapse
|