Cyclodextrin-Based Displacement Strategy of Sterigmatocystin from Serum Albumin as a Novel Approach for Acute Poisoning Detoxification

This study demonstrates that sterigmatocystin (STC) interacts non-covalently with various cyclodextrins (CDs), showing the highest binding affinity for sugammadex (a gamma-CD derivative) and gamma-CD, and an almost order of magnitude lower affinity for beta-CD. This difference in affinity was studied using molecular modelling and fluorescence spectroscopy, which demonstrated a better insertion of STC into larger CDs. In parallel, we showed that STC binds to human serum albumin (HSA) (a blood protein known for its role as a transporter of small molecules) with an almost two order of magnitude lower affinity compared to sugammadex and gamma-CD. Competitive fluorescence experiments clearly demonstrated an efficient displacement of STC from the STC-HSA complex by cyclodextrins. These results are a proof-of-concept that CDs can be used to complex STC and related mycotoxins. Similarly, as sugammadex extracts neuromuscular relaxants (e.g., rocuronium and vecuronium) from blood and blocks their bioactivity, it could also be used as first aid upon acute intoxication to encapsulate a larger part of the STC mycotoxin from serum albumin.

Automated summary

This study shows that sterigmatocystin (STC) can interact with cyclodextrins (CDs), with the highest affinity observed for sugammadex and gamma-CD. Molecular modelling and fluorescence spectroscopy revealed that STC inserts better into larger CDs. In addition, the study found that STC has a much lower affinity for human serum albumin (HSA) compared to sugammadex and gamma-CD, indicating that CDs can effectively displace STC from the STC-HSA complex.