Figure S7.

Metformin Increases Fatty Acid Oxidation to Regulate Host Metabolism and Lifespan, Related to Figure 7

(A and B) Quality of representation (measured as squared cosine) of the variables (Samples in (A) and metabolites in (B)) in the first three Principle Components. Value ranges between 0 and 1, where 1 corresponds to the maximum quality of representation.

(C–E) Worm lifespan extension by metformin is suppressed in fzo-1 (C) and eat-3 (D) mitochondrial fusion mutants and a drp-1 mitochondrial fission mutant (E) involved in mitochondrial homeostasis.

(F–I) Worm lifespan extension by metformin is suppressed in gas-1 (F) and nuo-1 (G) mitochondrial respiration complex I mutants, an isp-1 mitochondrial complex III mutant (H) and with RNAi knockdown of cco-1 encoding a mitochondrial complex IV subunit (I).

(J) Metformin does not further extend lifespan of worms treated with the FAO-inhibitor perhexiline (control plates supplemented with 0.25% DMSO).

(K) Worm lifespan extension by metformin is suppressed in a prx-5 peroxisomal biogenesis mutant.

(L) Worm lifespan extension by metformin is abolished by acetoacetate supplementation.

(M) Acetoacetate synergizes with metformin to inhibit E. coli OP50 growth. Significance stars represent metformin effect (purple) and metformin-acetoacetate interaction (green).

(N) Acetoacetate supplementation suppresses metformin-induced upregulation of worm Pacs-2::GFP expression in a concentration-dependent manner. Significance stars represent metformin effect (purple) and metformin-acetoacetate interaction (green).

(O) Acetoacetate supplementation suppresses metformin-induced upregulation of multiple worm lipid metabolism and FAO-related genes. Significance stars represent metformin effect (purple) and metformin-acetoacetate interaction (green).

(P) Suppression of metformin-induced upregulation of worm Pacs-2::GFP expression by acetoacetate is partially rescued by RNAi knockdown of Succinyl-CoA:3-Ketoacid-CoA Transferase OXCT-1/C05C10.3, a gene involved in the catabolism of ketone bodies including acetoacetate. This suggests that effect of acetoacetate partly depends on its utilization as metabolic fuel. Significance stars represent metformin effect (purple) and metformin-OXCT-1 interaction (green).

Data are represented as mean ± SEM. ^∗∗p < 0.01; ^∗∗∗p < 0.001. See also Table S1 for lifespan statistics and Table S7 for fatty acid metabolomics statistics.