Details

Autor(en) / Beteiligte

• Kluge, Stefan
• Schubert, Martin
• Schmölz, Lisa
• Wallert, Maria
• Birringer, Marc
• Lorkowski, Stefan

Titel

Bioactivity of Vitamin E Long-Chain Metabolites

Ist Teil von

• Vitamin E in Human Health, p.61-79

Ort / Verlag

Cham: Springer International Publishing

Link zum Volltext

Quelle

Alma/SFX Local Collection

Beschreibungen/Notizen

• Metabolic activation has been described as a key factor for the bioactivity of fat-soluble vitamins in the human body, except for vitamin E. During hepatic metabolism of vitamin E, the long-chain metabolites (LCMs) 13′-hydroxychromanol (13′-OH) and 13′-carboxychromanol (13′-COOH) are formed by oxidative modification of the side chain. These metabolites were detected in human serum, indicating a physiological relevance for the human body. Given that only 1% of the total body tocopherol is transported in blood, the determination of the LCMs in extra hepatic tissues is important for improving our understanding of the distribution of LCMs in the body. Therefore, enhancing current analytical procedures for the LCMs, with respect to detection sensitivity for substances in nanomolar concentrations, is indispensable. As a confirmation of their bioactivity, the effects of the LCMs on inflammation, lipid metabolism, cancerogenesis, and chemoprevention as well as xenobiotic metabolism have been studied. Although their exact modes of action are still unknown, there are several parallels between the regulatory actions of the LCMs of vitamin E and the active metabolites of vitamin A and D. Taken together, the recent findings provide evidence for a general concept of metabolic activation of the fat-soluble vitamins to regulatory metabolites, mediating various processes in the body.