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Updated: Aug 17, 2026

Light-driven Enzymatic Decarboxylation
Published on: May 22, 2016
[Stereoselectivity of skin carboxylesterase metabolism]
Quan-gang Zhu1, Jin-hong Hu, Hua-wu Zeng
1Department of Pharmacy, Changhai Hospital, Second Military Medical University, Shanghai 200433, China.
Aim:
To study the stereoselectivity of skin carboxylesterase metabolism and its molecular biological foundation for improving drug percutaneous absorption.
Methods:
Ketoprofen ethyl ester was used as a model drug, and skin homogenate was applied for studying the stereoselectivity of carboxylesterase metabolism. Human liver L02 cell was used as control of carboxylesterase expression, and RT-PCR was used for studying the expression of carboxylesterase.
Results:
The main metabolite of ketoprofen ethyl ester in human skin homogenate was R-ketoprofen. Human carboxylesterase-2 was highly expressed in skin and its cells. However, the expression of human carboxylesterase-1 was very weak or not detectable.
Conclusion:
Human carboxylesterase-2 is the main hydrolytic enzyme of prodrugs in percutaneous absorption, and shows metabolic stereoselectivity to prodrugs with chiral esters.
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