Published in:
01-03-2017 | Original Contribution
N- and S-homocysteinylation reduce the binding of human serum albumin to catechins
Published in: European Journal of Nutrition | Issue 2/2017
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Purpose
The dietary flavonoids epicatechin (EC), epigallocatechin (EGC), epicatechin gallate (ECG) and epigallocatechin gallate (EGCG) have been shown to interact with circulating albumin for transport in blood to different body tissues. This interaction may modulate their bioavailability and effectiveness.
Methods
Using affinity capillary electrophoresis to assess binding constants (K
b), we investigated whether posttranslational modification of human serum albumin (HSA) through N- and S-homocysteinylation, commonly observed in hyperhomocysteinemia, may modify its interaction with catechins.
Results
S-Hcy HSA had lower Kb values toward EC (14 %), EGC (18 %), ECG (24 %) and EGCG (30 %). Similarly, N-Hcy HSA had lower Kb values toward EC (17 %), EGC (22 %), ECG (23 %) and EGCG (32 %). No differences were observed in the affinity between catechins, albumin and mercaptalbumin.
Conclusion
Therefore, HSA posttranslational modifications typical of hyperhomocysteinemia reduce its affinity to catechins, potentially affecting their pharmacokinetics and availability at the active sites.