Fig. 6

Microbial communities associate with plasma and nerve lipidomics and transcriptomics. A–C Spearman’s correlation analysis heatmaps (FDR < 0.05) of relative abundance of PN-associated gut microbiota sensitive to dietary fat at 24 weeks of age with A plasma differentially altered lipids (DALs) (n = 11 animals), B sciatic nerve DALs [27] (n = 11 animals), and C sciatic nerve differentially expressed genes (DEGs) [27] (n = 11 animals), which are increased (up) or decreased (down) in HFD versus SD. ASVs at the genus or family (*) level that are higher in HFD are listed in black, and ASVs higher in SD are listed in blue. Correlation scale (red, positive; green, negative) is the same for (A–C). D Functional enrichment analysis of 64 increasing and 2 decreasing sciatic nerve DEGs [27] correlating with PN-associated bacteria using gene ontology (GO; left) and Kyoto Encyclopedia of Genes and Genomes (KEGG; right) (P < 0.05). The top ten biological pathways are shown. Bar plots indicate the proportion of DEGs assigned to each term (rich factor), with number of genes in each category indicated. CE, cholesteryl esters; CL, cardiolipins; DG, diglycerides; FFA, free fatty acids; lysoPC, lysophosphatidylcholines; lysoPE, lysophosphatidylethanolamines; PI-Cer(d18:1/22:0), N-docosanoyl-sphing-4-enine; Cer(d18:1/20:0), N-eicosanoyl-sphing-4-enine; Cer(d18:1/18:0), N-octadecanoyl-sphing-4-enine; PC, phosphatidylcholines; PE, phosphatidylethanolamines; PI, phosphatidylinositols; pPE, plasmenyl-phosphatidylethanolamines; SM, sphingomyelins; TG, triglycerides. ASV, amplicon sequence variant; FDR, false discovery rate; C, colon; Ce, cecum; I, ileum; P, pellets