title: Small-molecule targeting of the mitochondrial compartment with an endogenously cleaved reversible tag.
abstract: Targeted accumulation of chemically unaltered compounds within the mitochondrial compartment has not yet been achieved. Here we describe a reversible tag that is endogenously cleaved after mitochondrial accumulation has occurred. Specifically, we have reversibly tagged alpha-lipoic acid with a triphenylphosphonium moiety that is cleaved by the physiologically contained mitochondrial aldehyde dehydrogenase (ALDH-2). This reversibly tagged compound activates the lipoic acid-sensitive pyruvate dehydrogenase complex, and this results in increased glucose oxidation. We observed a reduction in ROS accumulation after preincubation with the reversibly tagged compound, whereas untagged or irreversibly tagged compounds either had no effect on ROS formation or rather caused increased oxidative stress, respectively. Lastly, the cytotoxicity of the reversibly tagged compound is less than that of the irreversibly tagged compound. Overall, reversible tagging combines decreased tag-related cytotoxicity with increased bioactivity, and this potentially provides a novel concept in mitochondrial pharmacology.
authors.affiliation: Department of Human Nutrition, Friedrich Schiller University Jena, Dornburger Strasse 29, Jena, Germany.
authors.forename: Jens
authors.initials: J
authors.lastname: Ripcke
authors.forename: Kim
authors.initials: K
authors.lastname: Zarse
authors.forename: Michael
authors.initials: M
authors.lastname: Ristow
authors.forename: Marc
authors.initials: M
authors.lastname: Birringer
mesh_terms: D000444:Aldehyde Dehydrogenase / Q000378:metabolism; D045744:Cell Line, Tumor; D005456:Fluorescent Dyes / Q000737:chemistry; D006801:Humans; D008928:Mitochondria / Q000201:enzymology* / Q000378:metabolism; D009943:Organophosphorus Compounds / Q000138:chemical synthesis / Q000737:chemistry* / Q000494:pharmacology; D011768:Pyruvate Dehydrogenase Complex / Q000378:metabolism; D017382:Reactive Oxygen Species / Q000378:metabolism; D008063:Thioctic Acid / Q000031:analogs & derivatives* / Q000138:chemical synthesis / Q000737:chemistry* / Q000494:pharmacology
chemical_list: D005456:Fluorescent Dyes; D009943:Organophosphorus Compounds; D011768:Pyruvate Dehydrogenase Complex; D017382:Reactive Oxygen Species; D008063:Thioctic Acid; D000444:Aldehyde Dehydrogenase