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Updated: Jun 8, 2026
06:08
Quantification of Hypopigmentation Activity In Vitro
Published on: March 6, 2019
Melanogenesis inhibition due to NADH
Francis Garcia-Molina1, Joseph Louis Munoz-Munoz, Mary Garcia-Molina
1GENZ: Investigative Group for Enzymology, Department of Biochemistry and Molecular Biology A, Faculty of Biology, University of Murcia, Murcia, Spain.
Bioscience, Biotechnology, and Biochemistry
|September 14, 2010
Summary
Nicotinamide adenine dinucleotide (NADH) affects melanogenesis by acting as a tyrosinase substrate, a suicide substrate, and in non-enzymatic reactions. This study kinetically characterizes NADH as a tyrosinase suicide substrate and irreversible inhibitor.
Area of Science:
- Biochemistry
- Enzymology
- Melanogenesis research
Background:
- Melanogenesis is a complex process regulated by tyrosinase.
- Nicotinamide adenine dinucleotide (NADH) influences melanogenesis through various mechanisms.
- Understanding NADH's role is crucial for pigment production research.
Purpose of the Study:
- To kinetically characterize Nicotinamide adenine dinucleotide (NADH) as a tyrosinase suicide substrate.
- To elucidate the kinetic mechanism of NADH oxidation by tyrosinase.
- To characterize NADH as an irreversible inhibitor of met-tyrosinase and deoxy-tyrosinase.
Main Methods:
- Kinetic characterization of enzyme-substrate interactions.
- Enzyme inhibition studies.
- Spectrophotometric assays to monitor reaction kinetics.
Main Results:
- NADH acts as a competitive substrate for L-tyrosine and L-DOPA.
- NADH functions as a suicide substrate, leading to irreversible tyrosinase inactivation.
- NADH non-enzymatically reduces o-dopaquinone.
- Under anaerobic conditions, NADH irreversibly inhibits met-tyrosinase and deoxy-tyrosinase.
Conclusions:
- NADH plays a multifaceted role in melanogenesis, acting as both a substrate and an inhibitor.
- A kinetic mechanism for NADH oxidation by tyrosinase has been proposed.
- NADH's irreversible inhibition of specific tyrosinase forms is confirmed.
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