Figure 5. Fructus Ligustri Lucidi (FLL) decreases the expression of FMO3 and the levels of circulating TMAO in aging mice. (A) The circulating TMAO levels quantified by LC/MS/MS. The expression levels of FMO3 were analyzed by immunohistochemical staining (B–C) and western blot (D) in the livers. (E–F) Correlation heat map indicating the association between the specific microbiota taxonomic genera and FMO3 expressions (E) and TMAO levels (F). Red indicates a positive association, blue denotes a negative association, and white manifests no association. a denotes a significant false discovery rate (FDR)-adjusted positive correlation at p values of < 0.05, and aa denotes a significant FDR-adjusted positive correlation at p values of < 0.01. b denotes a significant FDR-adjusted negative correlation at p values of < 0.05, and bb denotes a significant FDR-adjusted negative correlation at P values of < 0.01. Data are presented as mean ± SD. # compared with the normal group. * compared with the aging model group. p < 0.05 was considered statistical difference, n=8.