Itaconate is metabolized to 2-hydroxymethylsuccinate through a CoA-independent degradation pathway in mitochondria

Chen, F.; Hadam, L.; Dowerg, B.; Korotkov, V. S.; Jankowski, C. S. R.; Beutling, U.; Willenbockel, H. F.; Brandt, U.; Eva, M.; Fleissner, A.; Garritsen, H.; Jarek, M.; Franke, R.; Weichhart, T.; Broenstrup, M.; Neumann-Schaal, M.; Cordes, T.

doi:10.1101/2025.09.29.679238

bioRxiv · 10.1101/2025.09.29.679238

Itaconate is metabolized to 2-hydroxymethylsuccinate through a CoA-independent degradation pathway in mitochondria

Chen, F.·Hadam, L.·Dowerg, B.·Korotkov, V. S.·Jankowski, C. S. R.·Beutling, U.·Willenbockel, H. F.·Brandt, U.·Eva, M.·Fleissner, A.·Garritsen, H.·Jarek, M.·Franke, R.·Weichhart, T.·Broenstrup, M.·Neumann-Schaal, M.·Cordes, T.

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Abstract

The immunometabolite itaconate modulates cellular metabolism and is converted into structurally similar C5 dicarboxylates that require advanced analytics to decipher their metabolic fate. Here, we employ high-resolution mass spectrometry and tracing approaches and identify 2-hydroxymethylsuccinate (2HMS) as a previously unrecognized C5 dicarboxylate derived from itaconate. 2HMS synthesis occurs during inflammatory responses and upon itaconate treatment, as detected by 13C itaconate tracing. Pathway analysis reveals that methylglutaconyl-CoA hydratase (AUH) drives 2HMS synthesis through a CoA-independent conversion (CIC) pathway. This pathway is distinct from the CoA-dependent conversion (CDC) pathway that generates mesaconate and itaconyl-CoA influencing B12-dependent processes. In vivo inflammation studies reveal that adipose tissue prefers CIC to produce 2HMS and liver favors CDC-mediated mesaconate synthesis, highlighting tissue-specific itaconate degradation routes. This study identifies a new branch of itaconate metabolism, provides an analytical framework to resolve C5 dicarboxylate networks, and links 2HMS to inflammation and mitochondrial metabolism that might be targeted therapeutically.

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Chen, F., Hadam, L., Dowerg, B., Korotkov, V. S., Jankowski, C. S. R., Beutling, U., Willenbockel, H. F., Brandt, U., Eva, M., Fleissner, A., Garritsen, H., Jarek, M., Franke, R., Weichhart, T., Broenstrup, M., Neumann-Schaal, M., Cordes, T.. 2025-09-30. Itaconate is metabolized to 2-hydroxymethylsuccinate through a CoA-independent degradation pathway in mitochondria. https://doi.org/10.1101/2025.09.29.679238

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