Athways connected to host icrobiota interactions [28]. Amino acid metabolism and lipid metabolism have been the key pathways involving APP/PS1_CP mice and APP/PS1_CTRL mice within this study (Figure 4C). Specifically, capsaicin upregulated amino acid metabolism and downregulated lipid metabolism in APP/PS1 mice. Focusing on overlapping metabolites, we discovered four metabolites linked with tryptophan metabolism, which can be the vital aromatic amino acid. The relative abundances of 4 metabolites Kyn (p = 0.0043), 5-HIT (p = 0.0115), 5-HIAA (p = 0.0277), and indoxyl-Nutrients 2023, 15,8 ofsulfuric acid (p = 0.0281) enhanced significantly in APP/PS1_CP mice compared with APP/PS1_CTRL mice (Figure 4D). Lysophosphatidyl cholines (LysoPCs) and lysophosphatidyl ethanolamine (LysoPE) are linked with lipids metabolism.FGF-15 Protein Purity & Documentation Especially, LysoPC (17:0) (p = 0.0289), LysoPC (22:4(7Z, 10Z, 13Z, 16Z)) (p = 0.0188), LysoPC (16:0/22:six(4Z, 7Z, 10Z, 13Z, 16Z, 19Z)) (p = 0.IFN-beta Protein web 0008), LysoPC (19:0/0:0) (p = 0.PMID:23667820 0036), LysoPC (20:1(9Z)/0:0) Nutrients 2023, 15, x FOR PEER Overview eight of 17 (p = 0.0331), and LysoPE (0:0/22:0) (p = 0.001) decreased substantially in capsaicin-treated APP/PS1 mice (Figure S2).Figure 3. Relative abundance of gut microbiota in mice folks (all groups: n = 7). (A) BrayFigure three. Relative abundance of gut microbiota in mice men and women (all groups: n = 7). (A) BrayCurtis-based principal element analysis (PCA) plot of gut microbial communities in APP/PS1 Curtis-based principal element analysis (PCA) plot of gut microbial communities in APP/PS1 mice. (B) Bar plot displaying adjustments relative abundances at at phylum level in APP/PS1 mice mice. (B) Bar plot displaying modifications in in relative abundancesthe the phylum level in APP/PS1 mice treated with automobile or capsaicin. (C) Volcano plot displaying differences in gut microbiota treated with vehicle or capsaicin. (C) Volcano plot displaying differences in gut microbiota in between involving APP/PS1_CTRL and APP/PS1_CP. (D) Comparison on the modify A. muciniphila between APP/PS1_CTRL and APP/PS1_CP. (D) Comparison of the transform in in a. muciniphila among APP/PS1_CTRL and APP/PS1_CP. Outcomes are imply SEM. The minimum significance worth APP/PS1_CTRL and APP/PS1_CP. Benefits are mean SEM. The minimum significance worth was thought of as p 0.05. 0.05.three.five. The Correlation among Gut Microbiota and Serum Metabolites Research have identified that the relative abundance of A. muciniphila in APP/PS1 mice Spearman’s correlation analyses involving gut bacteria and serum metabolites with decreased with age [25]. Moreover, current evidence suggests that supplementation have been performed to investigate the links in between each sides. Atin the cerebral cortex observed A. muciniphila clearly decreased amyloid aggregation the phylum level, we and imthat Verrucomicrobiota significantly mice [26]. Within the present study, the higher abundance proved cognitive deficits and in ADchanged microbiota in capsaicin-treated APP/PS1 mice (p = 0.0002) (Figure 5A). Verrucomicrobiota had constructive correlations with Kyn, 5-HIAA, of species A. muciniphila in APP/PS1_CP versus APP/PS1_CTRL animals is important and 5-HIT. that is in agreement metabolites information. (Figure 3D),Kyn includes the threewith previousof tryptophan metabolisms. Additionally, Verrucomicrobiota was negatively correlated with lysophosphatidyl cholines (LysoPCs), such as LysoPC (17:0), LysoPC (16:0/22:six(4Z, 7Z, 10Z, 13Z, 16Z, 19Z)), LysoPC (19:0/0:0), 3.four. Capsaicin Upregulated Tryptophan Me.