Metabolomic analysis of plasma from metformin-treated humans, together with mechanistic studies in mouse models, reveals that metformin selectively inhibits mitochondrial complex I in the intestinal epithelium. This mechanism unifies multiple clinical effects of metformin, including enhanced intestinal glucose use, improved postprandial glycaemic control and increased production of GDF15 and N-lactoyl-phenylalanine.
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References
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This is a summary of: Sebo, Z. L. et al. Metformin inhibits mitochondrial complex I in intestinal epithelium to promote glycaemic control. Nat. Metab. https://doi.org/10.1038/s42255-026-01530-y (2026).
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Metformin lowers blood glucose by targeting intestinal mitochondrial complex I. Nat Metab (2026). https://doi.org/10.1038/s42255-026-01532-w
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DOI: https://doi.org/10.1038/s42255-026-01532-w
